It's understood a B-double truck collided with a tilt-tray truck just east of the Warrenheip petrol stations, on the west-bound lanes, just after 2pm on Monday. The tilt-tray truck then careered into the BP service station, crashing into bowsers.

The B-double came to a stop on the right hand lane nearby.

Fire crews were quickly on the scene, dousing vehicles with fire-suppressant foam and ensuring the petrol pumps were switched off.

Inside, witnesses said all they saw was a truck barrelling towards them.

Dan from Miners Rest, who asked not to use his surname, said he was waiting for a coffee with his 15-year-old daughter when they heard a loud noise from the freeway.

"Next thing, there's a truck heading towards us," he said.

"We saw a door for the staff, I grabbed her, it was about to bolt through (the front of the petrol station), then it hit the bowser."

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Once he was sure his daughter was safe, Dan raced out to help the tilt-tray truck driver, who he said was unconscious.

"But 20 seconds later, he started groaning," he said.

"I said I think he's still with us, then a big fella ripped the door open, undid his seatbelt and carried him onto the grass.

"I think it's the most horrific thing (my daughter) has ever experienced - it just happened so quick."

Another man, who asked not to be named, was filling up his car when the truck crashed into the bowser next to him.

"It was quick - I jumped out of the way, just went flying, there was stuff everywhere," he said.

"I feel like I've cheated death a bit today."

An Ambulance Victoria spokesperson confirmed a man in his 60s was taken to the Ballarat Base Hospital in a stable condition with upper body injuries.

The condition of the B-double driver is not known, nor is it known what caused the incident.

The tilt-tray truck was completely destroyed, with damage to its rear and a fully crumpled cabin.

The B-double had a shattered windscreen, and severe damage to its front left fender.

Other slightly damaged cars were seen being towed away from the service station - the bowser was also destroyed, and some damage to the kerb outside the service station was also seen.

A significant amount of petrol was spilled following the crash, which was cleaned up by the CFA.

The BP petrol station was reopened last year following renovation works, including the installation of a truck shelter.

Later that afternoon, emergency crews were called to a car and truck collision on the Daylesford-Trentham Road near Musk about 4.30pm - two people in their 70s were taken to Ballarat hospitals in stable condition, both with upper body injuries.

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