EMBED >More News Videos Santa Anita Park reopened its inner-exercise track in Arcadia on Friday and instituted new rules after 21 horses died over the last two months at the park.

ARCADIA, Calif. (KABC) -- Santa Anita Park is scheduled to resume horse racing on Friday, racetrack officials confirm.The track is set to reopen after a deal was made Saturday by track officials and the Thoroughbred Owners of California. Part of the deal includes a ban on the drug Lasix, which will now be delayed until next year. Lasix is a diuretic that helps prevent horses from hemorrhaging, according to the Daily Racing Forum.Racing at the park had been suspended indefinitely after the number of Thoroughbred deaths started to skyrocket since late December. A total of 22 horses have died due to injuries on the track.The Los Angeles County District Attorney's Office said Friday that it is joining an investigation surrounding the 22 horse deaths at Santa Anita Park.The DA confirmed that it has assigned investigators to work with the California Horse Racing Board.Meantime, there is a call for a congressional committee to investigate treatment of racehorses. Congresswoman Judy Chu wants the House Energy and Commerce Committee to investigate the treatment of horses, not only at Santa Anita but at racetracks across the country.The park announced this week that the track would ban race-day medication and the use of riding crops. The Lasix ban was one of several changes to Santa Anita policies announced.But the Thoroughbred Owners of California and the California Thoroughbred Trainers -- which both support the use of Lasix -- balked at the ban, according to the DRF, and it will now begin with next year's crop of 2-year-olds. Additionally, race-day administration of Lasix will be reduced from a maximum of 10 CCs to 5.PETA issued on statement late Saturday, saying Thoroughbred owners are like Lasix addicts and "if one more horse dies, there will be blood on the owners' hands and hell to pay."Read the full statement here: