Two horses died following a head-on collision during training Thursday, a day after the start of the 2019 Del Mar racing season.

The horses and their jockeys were on the track at about 6:45 a.m.

“There were three horses breaking from the starting gate," Director of the Del Mar Thoroughbred Club Joe Harper said. “The horse made a U-turn, that was galloping.”

Charge A Bunch with jockey Geovanni Franco turned and ran head-on into Carson Valley and jockey Assael Espinoza, DMTC said.

“Both [horses] suffered cervical fractures and both were dead on the racetrack,” Dr. Rick Arthur said.

Arthur, Equine Medical Director at UC Davis School of Veterinarian Medicine, is assigned full-time to the California Horse Racing Board.

Both men said the safety protocols for training on the track during morning workouts were being followed at the time of the collision.

“There was no outside influence to make these horses do what they did,” Harper said.

“Horses run into each other [on] tracks, in the farm, out in the wilderness,” he said. “This is just one of those thankfully very rare, unfortunate accidents.”

Within hours, PETA's Senior Vice President Kathy Guillermo was calling for the CHRB to launch an investigation.

"Saying that deaths are inevitable in racing is like saying a swim team can't compete without drowning. If racing can't be done without horses dying, it shouldn't be done at all," the statement read in part.

The bodies of the horses will be sent to a lab in San Bernardino to determine more details on their fatal injuries, Arthur said.

Both jockeys were thrown from their horses but were described as "fine" by the track officials.

The racing season opened Wednesday under a shroud of controversy following a series of horse deaths at Santa Anita Racetrack in the Los Angeles area. Their racing season ended with 30 horse deaths and the banning of Hall of Fame trainer Jerry Hollendorfer.

In response, DMTC officials said numerous changes were made at the track to ensure horse safety, including on-site veterinarians during morning training.

The racetrack did have veterinarians and emergency personnel on site at the time of the accident, so response was immediate, DMTC said.

A statement from the club said, "We are deeply sorry for the horses and their owners, trainers, riders and grooms."

Bob Baffert, Carson Valley's trainer, released the following statement in response to his horse's death:

"This was a very unfortunate accident and it is a shock to everyone in the barn. We work every day to take the best care of our horses but sometimes freak accidents occur that are beyond anyone’s ability to control. This is one of those times and we’re deeply saddened for the horses and everyone involved."

Please refresh this page for updates on this story. Details may change as more information becomes available.