One person was killed and four others were hospitalized Monday morning after a head-on collision in Julian, according to ABC 10News.

The crash was reported about 6:56 a.m. at 3415 Pine Hills Road, several miles south of state Route 79, ABC 10News reported, citing the California Highway Patrol. Cal Fire San Diego said responders arrived to find one of the two vehicles partly engulfed in flames.

Authorities had not determined what led to the crash as of Monday. One person died at the scene, while one victim was listed in critical condition and another in moderate condition. Two additional victims were taken to hospitals with injuries of unknown severity, according to the report.

For Santee and East County drivers, the crash involved a rural backcountry route that residents may use when traveling between inland communities, mountain areas and Julian.

Investigators are expected to continue reviewing the circumstances of the collision. Officials had not released the names of those involved by Monday afternoon.