Fourth horse dies in training at Del Mar

DEL MAR, Calif. -- A fourth horse has died in training at Del Mar.

A spokesman for the track located north of San Diego confirmed Monday's fatality.

Bri Bri, an unraced 3-year-old filly trained by Jim Cassidy, sustained a broken pelvis after a workout under exercise rider Abel Hernandez, who wasn't injured.

It's the fourth death since the summer meet began July 17. The first two deaths came July 18, when horses collided, and the third was a breakdown July 29 on the main dirt track. There have been no deaths in 171 races.

Cassidy also had a horse die during Santa Anita's recent winter-spring meet, in which 30 horses died.