Last updated on .From the section Horse Racing

Protestors gather outside the Santa Anita race track

Racing at a California track has been suspended indefinitely by its owners after 21 horses died in 10 weeks.

The Santa Anita Park in Los Angeles has hired former track superintendent Dennis Moore to help lead a study of its dirt surface.

The California Horse Racing Board is also investigating the matter.

"The safety, health and welfare of the horses and jockeys is our top priority," said Tim Ritvo, chief executive of owners the Stronach Group.

"We feel confident in the track and we're just being very proactive.

"We want to do all the testing that needs to be done, and when we believe we're in good shape, we'll start to train over it again."

The most recent death was Lets Light the Way, a four-year-old filly who was put down after injuring her front right leg on the track on Tuesday.

It was the ninth death following an injury sustained in training on the main dirt track, a toll that also included 2017 Breeders' Cup winner Battle Of Midway.

The park conducted tests on the track last week, but having analysed data and examined the track, nothing unusual was found and it was cleared for racing.

The suspension of racing comes before what would have been a big weekend for the park, which was set to host the Santa Anita Handicap and the San Felipe Stakes.

People for the Ethical Treatment of Animals (Peta) president Ingrid Newkirk agreed with the decision to close the track and added that Peta would also like to see a criminal investigation into the matter.