ARCADIA (CBSLA) -- Authorities said the 23rd horse since late December was euthanized Sunday at Santa Anita Race Track.
Racing had only resumed there Friday after a month-long closure. During the closure, new regulations were put in place and the track was examined for faults.
None were found.
But as KCAL9's Jeff Nguyen reports seeing video of the horse falling during race number four Sunday is "painful to watch."
The video of the race was provided to him by videographer Daniel Barcenas.
"It just broke our heart right there," he said, "our hearts sank."
He told Nguyen he and his family have been coming to the track for years. But after the deadly fall they did not stick around for the rest of the day's races.
"We don't want to be a part of that anymore," Barcenas said, "It hurts us to see that happen to the horses."
The horses were making a turn from grass to dirt when the horse -- named Arms Runner -- went down.
A second horse -- La Sardane -- tripped over Arms Runner. But the second horse was not hurt. Arms Runner, a 5-year-old gelding -- had to be euthanized.
"They were coming down the hillside turf course," said racing fan Carl Macarelli, "and everything was fine. The one horse was leading, the big favorite, and then they hit the dirt and when they hit the dirt I saw the gray horse and another horse go down."
Julie Doran also witnessed the tragedy.
"All of a sudden we saw horses go down," Doran said, "and with what's been going on, it was kinda sad to think. We couldn't even focus on the rest of it. It took a while. And everyone was -- especially the kids. They were really upset seeing what was going on."
Our cameras were there for race number eight, when a jockey -- Heriberto Figueroa -- fell off his horse. Santa Anita said he is doing fine Sunday evening.
Meanwhile, animal rights advocates PETA asked Governor Newsom to intervene.
"PETA calls on Governor Newsom to urgently form an independent panel to investigate the training and veterinary practices in California racing if the California Horse Racing Board does not take every possible action to protect the horses, then racing should not be allowed to continue."
Races are expected to continue at the track on Thursday.
The track told Nguyen that, at this point, races are going on as scheduled.
The LA Times reported that Arms Runner was owned by Rockingham Ranch of Sherman Oaks.
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