San Francisco,  A total of 25 police recruits were injured during a training run after a vehicle rammed into them in California, authorities said.

The incident took place on Wednesday when a 22-year-old wrong-way driver plowed his car into a class of 75 recruits, who were running in formation as part of a training exercise, reports Xinhua news agency.

Five of the injured were in critical condition, four in moderate and stable condition and 16 sustained minor injuries, said Los Angeles County Sheriff Alex Villanueva.

The vehicle veered into the group of recruits from the Los Angeles County Sheriff's Department and several other police departments in Southern California at around 6.20 a.m. in Whittier, Villanueva said at a news conference.

Officials said the young driver suffered minor injuries and was detained at the scene.

Villanueva said the driver passed a field sobriety test and the cause of the accident "is still unknown at this time".

Officials said that the investigation is still ongoing.