LA County DA's Office joins investigation surrounding Santa Anita horse deaths

ARCADIA, Calif. (KABC) -- The Los Angeles County District Attorney's office is joining an investigation surrounding the 22 horse deaths at Santa Anita Park.

The DA confirmed Friday 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 at Santa Anita Park following the deaths.

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.

MORE: Santa Anita Park creates new health and safety rules

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.

Racing at the park has been suspended indefinitely after the number of Thoroughbred deaths started to skyrocket since late December. The park also announced the track would ban race-day medication and the use of riding crops.