Two people were injured today when two vehicles collided head-on in Chatsworth, authorities said.

It happened about 1:20 a.m. at Topanga Canyon Boulevard and Santa Susana Pass Road, said Officer M. Puno of the Los Angeles Police Department’s Valley Traffic Division.

One man and one woman were injured, said Officer Brian McClary of Valley Traffic. The drivers were the only occupants of the cars.

Investigators at the scene determined alcohol was not involved in the crash, McClary said. The driver going downhill drifted over the double-yellow lines on the windy road.

The crash remained under investigation.