For a man whose words have whipped up a political and media storm in Australia, Yousif Ibrahim Fasher has been remarkably untroubled by visits from journalists. Or, for that matter, authorities.

It was Fasher who alleged a month ago that three asylum seekers had their hands deliberately burned by the Australian navy during its second operation to tow back an asylum vessel to Indonesia in January.

But since then, as the storm raged on, he was left largely alone. This week, in the Tanjung Pinang immigration detention centre on a little island off the coast of Sumatra, that changed. Fairfax Media conducted the first extended face-to-face interview with Fasher, who says he was an eyewitness to the incident, and he told his story in unprecedented detail.

His account has been consistent from the first. He says he has no doubt that what he saw at close quarters on about January 3 was three people's hands being deliberately held to a hot exhaust pipe by Australian naval personnel to punish them for protesting, and to deter others from doing one simple thing: going to the toilet too often.

They are allegations which, when given credence and air time by the ABC, encouraged the Abbott government and Rupert Murdoch's News Limited to open a culture war with the national broadcaster, to review its funding and question its reach into Asia.

The Australian navy and government robustly denied Fasher's allegations and have repeatedly done so since.

''Who do you believe?'' asked Prime Minister Tony Abbott last month. ''Do you believe Australian naval personnel or do you believe people who were attempting to break Australian law? I trust Australia's naval personnel.''

Navy Admiral Ray Griggs tweeted on January 22: ''Based on everything I know, there is no basis to these allegations - none.''

The Minister for Immigration and Border Protection, Scott Morrison, dismissed the allegations on Thursday without responding specifically to a detailed list of written questions about the alleged ''burned hands'' incident. He said navy and Customs personnel had clear guidelines on appropriate behaviour and ''I know and trust'' they would behave in an appropriate manner.

''The government does not give credibility to malicious and unfounded slurs being made against our navy personnel and rejects outright any allegations of unprofessional conduct by our people serving in Operation Sovereign Borders. If media outlets wish to give credibility by publishing such unsubstantiated claims, that is a matter for them,'' Mr Morrison said.

Fasher, though, says he has no motive to lie. Quite the reverse; he believes telling his story may harm his chances of being granted permanent refuge in Australia. He is willing to talk to Australian authorities, but none so far has sought to ask him questions.

He has also gone further: he has reiterated other allegations, also made early in his return to Indonesia, but which, out of deference to navy denials, the Australian media has not until now reported. On Fasher's account, the naval sailors who rotated on to and off the wooden fishing vessel carrying 45 people restricted the passengers' access to the toilet from the first day of the operation, January 1. Women were allowed to go once a day, at night time, and the men during the day.

A low corridor ran from the cabin where most of the passengers stayed, past the engine room to the rear of the boat where the toilet was located. Fasher demonstrated how he had to stoop to walk down this corridor. Four naval personnel guarded its rear entrance and two guards stationed in the main cabin restricted entry to it from that end.

Across the narrow corridor, low to the ground, were three exhaust pipes, running fumes from the engines out the side of the boat to the open air. Passengers had to step over them to get to the toilet. Only one engine was working - the navy fixed it on the third day of the tow-back - so only one exhaust pipe was hot, Fasher said.

On that same day, a group of four men were protesting against the toilet strictures. Fasher was the navy's go-to man for translation, and was in the main cabin interpreting. As the argument heated up, he says the four asylum seekers forced their way past the two guards in the main cabin to try to get to the toilet. Those guards followed them in, and the guards at the other end also entered the corridor to stop them. There was an altercation, which Fasher said he was watching from outside.

During the turmoil he says a young man, Bowby Nooris, the first into the corridor, was sprayed in the eyes with capsicum spray, stumbled and blindly grabbed at the hot pipe.

This is consistent with Nooris's injuries, and what he has subsequently told both the ABC and The Australian about how they were incurred. It's the basis of the conclusion by Media Watch that: ''It appears that the burns occurred in a scuffle with the navy and were not deliberately inflicted by navy personnel''.

But Fasher insists that, after Nooris fell, naval personnel - he does not know their names - grabbed the wrists of three other men and forced their hands on to the hot pipe, one after the other. He demonstrates how he says it was done.

''I saw it with my eyes because I was translating . . . They punished three of them, three of them . . . so they would never want to go to the toilet again,'' Fasher said.

Afterwards, he says, a man in navy uniform called him over.

''They said: 'Yousif, translate for the people. Say to anyone: if you want to go to the toilet again, we will burn his hands. So, tell them.' So I translate for them.''

Apart from those three and Nooris, Fasher says a fifth person, his own wife, suffered burns. She fell on the pipe after being pushed by a member of a naval boarding party and was burned on her arm.

Abdullah Ahmed, from Eritrea, was on the same boat. He admitted he had not seen the incident because he was on the top deck, but the hand-burning story had immediately spread among the passengers. ''I saw people with burned hands . . . They said: 'Don't go to the toilet, it's punishment . . . from the navy','' Ahmed said.

Fasher and Ahmed allege that, for the remaining days of the journey, the navy refused medical treatment for the burns, telling people to lie down and drink water.

Missing from the story so far is testimony from the three men whose hands were allegedly deliberately burned. Two of them, Nour and Moustafa, refused multiple requests to speak of their experiences. Fasher says they are afraid.

''They're afraid that if they say the truth, maybe Australia will not accept them, maybe they will not be accepted through the UN.''

The third, Somalian Mohammad Ar, did finally agree to an interview with Fairfax Media at the Kupang hotel where he was still being held late last week. But though we travelled from one end of the Indonesian archipelago to the other to take up his offer, Indonesian immigration officials prevented that interview from taking place inside the hotel because it was ''against regulations''. An English-speaking intermediary, Faisal Hussein, said Ar was too scared of reprisals from heavy-handed officials to come outside the hotel to speak.

Allegations of five people burned - three deliberately and two as a result of rough treatment - remains short of the seven claimed in the ABC reports, which was one of the elements that prompted Media Watch to accuse it of over-reach. The ABC has issued a statement admitting its wording could have been ''more precise''.

But, Fasher says he witnessed three people who have had pain deliberately inflicted on them by Australian personnel. If it seems unlikely or bizarre that naval personnel would deliberately restrict access to the toilet on a vessel under their control, it's not the first time the allegation has been made.

In 2003 an Afghan asylum seeker, Abbas Ali Changizi, alleged that, on a 2001 navy interception, ''passing water'' was strictly controlled by sailors aboard his boat, and asylum seekers asking to do so were mistreated. Abbas made a police statement at the time, and his claims were investigated. They were later dismissed as unsubstantiated.

Mr Fasher is aware that his story has been heavily disputed in Australia, but says he has no motive to lie. ''Why people would burn their hands by themselves? . . . If [it was only] one person you could say an accident, but five people?''

Some of the navy personnel, though by no means all, had also been rude and insulting, he said.

''They said: 'F--- you . . . You choose to come from your country, we don't ask you to come'. To the black Africans, one said: 'Oh, you're a monkey from Africa'.''

Fasher has also made two other specific allegations. From early in January, he has told media organisations, including Fairfax Media, about four young men whom he says went overboard from their wooden vessel in the hours before the navy found their boat off Darwin. He claims naval crews were told of the tragedy, but did not appear to make any attempt to search for the missing men.

Fasher, backed by Ahmed, says the four - two Somalians, one Sudanese and one from Yemen and all relatives of other passengers - had fallen overboard in heavy weather when the boat was only 37 kilometres from Darwin. It was the only thing, Fasher says, that prompted them to divert their course to a nearby island and call authorities.

''Why would we land down on the island? [Otherwise] we would have continued because we had fuel, we had one engine working and it was only 37 kilometres to Darwin. Why did we call people [for help]? Because . . . we lost people.''

However, Mr Fasher said the navy showed little sign of searching for the missing men, one of whom was his cousin, Usman Ali Fasher, 23, or their bodies. The naval first responders who dealt with the group told them they had to leave the island because crocodiles made it dangerous, and that their boat was safer, Fasher said.

''They said they were going to look for [the missing men] and when we kept asking questions, they said: 'We'll never go anywhere until we have found your friends and brothers'.'' Fasher has since heard no news of the missing men, including his cousin. He now presumes them drowned.

Mr Morrison said on Thursday the government was aware ''of claims that four people may have fallen overboard from a suspected illegal entry vessel inside Australian waters'' on Tuesday January 7, 2014. ''These claims were rigorously assessed and acted on at the time they were made, and I am confident that they were not true. It is important to note that the claimed incident occurred well before the suspected illegal entry vessel had been intercepted by Australian authorities. For operational security reasons, the government will not go into further detail on this matter,'' Mr Morrison said.

The second previously unreported allegation concerns the apparently imminent finding by the Australian navy that its ships, in the words of Mr Abbott, fumbled their way into Indonesian waters as a Test cricketer might drop a catch.

Fasher and Ahmed say that for the last two nights of their tow-back, January 4 and 5, the two Australian navy vessels turned off their lights. An Australian navy source has said this would never happen and is against the law of the sea.

However, the account is consistent with that of another asylum seeker, Abdirashid Mohamed, who was quoted in the Indonesian press on January 8 - well before the Australian government admitted to border incursions - saying the lights on the ships were extinguished and the asylum boat returned very close to shore. That report suggested the reason was to avoid detection by Indonesia.

Fasher said the asylum seekers had their own GPS device, which showed their position after being released by the naval ships, as 14 kilometres (7.5 nautical miles) off the shore of Rote Island - well within the 12-nautical-mile Indonesian nautical limits territory.

Anwar Salih, a passenger on the first boat to be turned back by Australia - on December 19, 2013 - told Fairfax Media that his boat also had sailed very close to shore with lights of the accompanying naval vessels extinguished.

Asked if it were possible the ship's captains had deliberately gone closer to Rote Island to try to ensure the safety of the people they were putting back, Customs and Border Protection referred Fairfax Media to Mr Morrison's January 17 press conference in which he apologised for ''inadvertent incursions'' into Indonesia.

Follow us on Twitter