The large truck appears to have careered through the roundabout in the centre of town, crashing into a smaller car, tearing through a tree and also smashing into a smaller roadworks truck.

Senior Constable Grant Egan from the Ballarat Highway Patrol said investigations into the cause of the crash are ongoing.

"There's been a B-double truck lose control coming (down the hill) into Buninyong," Senior Constable Egan said.

"(The driver) has taken measures to avoid a collision...he's come across onto the wrong side of the road to avoid any further vehicles."

The smaller truck was tipped on its side while the larger truck sustained serious front end-end damage.

The crash occurred about 2.40pm, with the truck eventually coming to rest next to the old Post Office.

All roads leading into the roundabout were blocked as emergency crews attended the scene.

There were multiple ambulances, police and CFA vehicles at the scene.

A witness to the incident, concreter Brendan Hicks, estimated he was only 20 metres away from the incident.

"It was a bang, bang, then a big crack and pop - that was the sound of the tree exploding basically, it hit the tree that hard it exploded," he told The Courier.

"I was just thankful I'm still alive and thankful we're all still alive.

"I'm gonna go buy a Tattslotto ticket and give the missus a cuddle and a kiss."

Paramedics assessed three people at the scene for non-life threatening injuries.

Two people have been taken to Ballarat hospital in a stable condition.

It is the second truck crash at the roundabout in less than a month.

Senior Constable Egan said the incident is a good reminder for drivers to be aware of their surroundings while on the road.

"The people have done pretty well here to avoid being involved in the collision."

In April a large truck rolled while trying to turn at the roundabout, causing a mass spillage.

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