Five of the NCOs are in critical condition, with the most serious injuries being loss of limbs, broken bones and head injuries.
Four others have described injuries as “moderate”, while another 16 suffered minor injuries.
The shocking scenes unfolded around 6:30 a.m. Wednesday in Southern California, as a group of 75 law enforcement recruits went about their morning drill.
Footage shows a written-off vehicle with severe damage to the hood and front bumper as firefighters, medics and detectives investigate the road.
The driver, whose identity is not known, has been detained by police.
“We are certain we have a 22-year-old male driver who drove the wrong way and into the classroom,” Sheila Kelliher, a spokesman for the Los Angeles Fire Department, said Wednesday morning.
Aerial footage of the Whittier scene showed running shoes and backpacks lying on the ground.
Sheriff Alex Villanueva said the Honda CRV involved looked “like a plane wreck” after the incident, which also saw it crash into a pole.
Sheriff Villanueva said: “It’s hard to see because these young people are getting ready to put themselves at risk in their careers, and who knows while you’re training to do that, you’ve put yourself at risk. ” way.
“So my heart goes out to all of them as they pursue this career. I hope they all recover quickly and are in good shape.”
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All the sheriffs-in-training, who were in their eighth week of training, were wearing reflective vests when they were hit.
One of the injured is in hospital on a ventilator.
The Los Angeles Police Department offered its support to the interns affected by the crash.
In a statement, it said: “Our thoughts are with those affected by this morning’s events involving the sheriff’s recruits.
“While we await more information on their condition, we wish everyone a speedy recovery.”