Shane Middleton, 26, who is alleged to be the Mongols' sergeant-at-arms, and Renee Comeadow, 27, were on Thursday morning arrested at their Seabrook home during a raid in which police seized ammunition, firearms components, drugs and 3D printers.

Mr Middleton's brother, Simon, 29, was also arrested at his Oakleigh South home on Thursday morning, when an allegedly stolen motorcycle was seized.

The Middleton brothers and Ms Comeadow were later charged with various offences and faced Melbourne Magistrates Court on Thursday afternoon, where all men were remanded in custody.

The trio are all charged with attempting to pervert the course of justice.

Police allege they tried to intimidate and pressure a man, who is a prosecution witness in a criminal case, to withdraw his statement.

Shane Middleton is also charged with possessing a Taser, possessing cocaine and committing an offence while on bail.

His brother is charged with theft, receiving stolen goods and dealing with the suspected proceeds of crime.

Ms Comeadow is also charged with committing an offence while on bail.

She applied for bail on Thursday, when the court was told she was desperate to be back with the couple's young daughter.

Magistrate Peter Dunn was told police were concerned Ms Comeadow would contact prosecution witnesses and offend if released from custody, and refused her application. Ms Comeadow cried when her bail was refused.

Shane Middleton, renowned for his striking facial tattoos, did not apply for bail. He and his fiancee are due to return to court in September.

Simon Middleton is due to apply for bail on Monday.

During Thursday's raids in Seabrook and Oakleigh South, police also seized an imitation firearm, along with vials of steroids and white powder that is believed to be cocaine.

Shane Middleton was shot in the leg in November, but it is unclear who shot him. He was driven to Sunshine Hospital by Ms Comeadow.