U.S. Sen. Dianne Feinstein, D-Calif., called for the famed Santa Anita Park outside of Los Angeles to be temporarily shut down after another horse died at the course over the weekend, the 26th such thoroughbred fatality there since Christmas.

California's senior senator urged the drastic action after Kochees, a 9-year-old gelding, was euthanized Sunday, marking the third horse death in just nine days.

"How many more horses must die before concrete steps are taken to address what is clearly an acute problem?" a statement from Feinstein said.

She said track conditions and the history of each of the horses' medications have to be carefully scrutinized.

"We need a thorough investigation of practices and conditions at the track before any more races are held," Feinstein said. "I believe we need to carefully review what medications horses are given and under what circumstances, as well as take a close look at the issue of overrunning horses, which may be contributing to deaths."

Representatives for Santa Anita and the track's owner in Canada, the Stronach Group, declined immediate comment Tuesday.

But reps for the industry's advocacy group, the National Thoroughbred Racing Association (NTRA), said Santa Anita shouldn't be forced, even temporarily, out of business.

The track's owners and California regulators "are addressing Sen. Feinstein’s concerns regarding the practices and conditions at Santa Anita Park," according to a statement by NTRA CEO Alex Waldrop.

In the latest incident, Kochees was injured during the track's sixth race Saturday. Jockey Mario Gutierrez detected a problem following the far turn and Kochees was eased out of running before reaching the top of the stretch.

The 26 deaths matches the same number of fatalities from Santa Anita's 2017-18 season.

But last year's total came after a full season of 758 races and 5,960 starts by horses, according to the California Horse Racing Board. This year's 26 deaths at the Arcadia track came after just 626 races and 4,636 starts, the regulation body said.

Feinstein suggested that horse racing could be on its last legs in the United States.

“Tracks in the United States have significantly higher rates of death than tracks overseas," according to Feinstein. "We need to determine what we’re doing wrong in this country and fix it. If we can’t, we need to consider whether horse racing has a future here.”

The People for the Ethical Treatment of Animals has been calling for Santa Anita's shutdown since the start of this run of thoroughbred deaths. PETA Senior Vice President Kathy Guillermo renewed that call after Kochees' death.

"Santa Anita and all California tracks must suspend racing until the ongoing investigation by the district attorney is complete and the new rules have been strengthened," Guillermo said. "Nothing short of a zero-fatality rate is acceptable."

The track has said earlier that it has done everything possible to account for track conditions, including a weekslong shutdown in March as authorities studied the racing surface and investigated whether heavy rains this past winter might have weakened the course.

Races resumed after the state horse racing board approved a series of safety measures, including limits on certain types of medications administered to horses.

"We need to give these safety reforms the chance to succeed," according to Waldrop, the NTRA's CEO.

Santa Anita is set to play host to the Breeders' Cup races Nov. 1-2.