Three vehicles parked outside at a Fitchburg apartment complex were heavily damaged when one of the vehicles caught fire and the fire spread to the other vehicles.

Nobody was injured in the fire reported around midnight at 5451 Williamsburg Way, site of the New Fountains apartments, Fitchburg Fire Department officials said.

Witnesses said one vehicle was on fire at first, with the fire spreading to adjacent vehicles.

The apartment building was not affected by the blaze.

No cause of the fire was determined, and no damage estimate was released by the Fitchburg Fire Department.

The fire is under investigation.

Fire officials said the fire does not appear to be suspicious at this time.