summarize this text: Trainer NAME_1 NAME_2 has been suspended after two of his horses died in the lead-up to Saturday's 149th Kentucky Derby.

Parents NAME_3 and Chasing Artie collapsed and died at the Churchill Downs track, with the cause of death still unknown.

Another of NAME_4's horses, NAME_5, has been scratched from the race following his suspension.

Four horses have now died in the build-up to America's most celebrated race.

The suspension prohibits NAME_4, or any trainer directly or indirectly employed by him, from entering horses in races or applying for stall occupancy at all Churchill Downs Incorporated (CDI) owned racetracks.

"Given the unexplained sudden deaths, we have reasonable concerns about the condition of his horses and decided to suspend him indefinitely until details are analysed and understood," said NAME_6, the CDI president and chief operating officer.

"The safety of our equine and human athletes and integrity of our sport is our highest priority. We feel these measures are our duty and responsibility."

Take Charge NAME_7 and NAME_8 On Ice, trained by NAME_9 and NAME_10 respectively, both had to be put down down after suffering leg injuries at the track in Louisville earlier this week.

CDI says it is working with regulators to investigate the circumstances behind the deaths.

An earlier CDI statement prior to NAME_4's suspension described the deaths as "completely unacceptable" and that "these troubling incidents are alarming and must be addressed."

Practi The words with all capital letters should appear at least 14 times.
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