SANTA ANITA (CBSLA) — Another horse has died at Santa Anita Park, increasing the number of racing or training deaths going back to the 2018 season to 69, and 33 since December.

A 5-year-old gelding named Kentucky Colonel collapsed and died from an apparent heart attack after jogging around the racetrack Saturday afternoon.

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The gelding’s trainer, Richard Mandella, told reporters the horse had recently returned to racing after being away for a rest. Colonel had five wins in 20 career starts. He last raced in May at Golden Gate Fields in Northern California.

Employees and supporters for horse racing rallied on Saturday outside of Santa Anita Park’s main entrance, holding signs. They expressed their love for horses and support for jobs and the lifestyle the industry affords.

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But protesters have been at the same spot in recent months criticizing the horse deaths at the track. They are pushing to end the sport.

Kentucky Colonel’s death marks the 33rd since December, and 69th since the beginning of the 2018 season.

The causes of the various horse accidents remains under investigation.

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(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)