Fire crews were called to the Balwaren Motel at 1.10am to find the unit engulfed, causing an estimated $100,000 damage.

A Mitsubishi wagon parked nearby at the Western Highway site was also set alight, causing extensive damage.

Six fire crews from Ballarat, Warrenheip and Bungaree brought the fire under control by 1.30am.

Ballarat Police Acting Sergeant Scott McLoughlin said police evacuated residents from the units.

Investigations were continuing yesterday, with arson chemists called to examine the scene.

Motel owner Gabrielle Mueller said she was woken by residents banging on her door.

``I went out and unit number two was in flames, as was the car in front of number 14,'' she said.

Ms Mueller's partner, Frank Rogers, 70, was taken to Ballarat Health Services Base Hospital with smoke inhalation. He was last night in a stable condition.

Resident Sharron Fitzpatrick, whose unit was next to the burnt car, was also woken by a neighbour.``We freaked and ran, leaving everything, thinking that the car was going to blow and go straight into my unit,''