A total of seven horses have died at Churchill Downs, the home of the Kentucky Derby, over the past week in the lead-up to the race, the authorities announced Saturday.

The unprecedented death toll has prompted an investigation and a massive outcry from animal rights activists.

Joseph Grove from Animal Wellness Action expressed concerns over the alarming death toll.

"As a native Louisvillian, I get the passion people here and across the country feel about this iconic race," Grove said in a statement, according to NPR. "But the care of the horses must be our first priority, and this cluster of horse deaths is startling. Lamentations are not enough."

The first death took place on April 29 when a 3-year-old gelding named Code of Kings broke his neck before a race. According to his trainer, Tim Glyshaw, the horse seemed fixated on the lights at a nearby DJ booth before the incident, Daily Racing Form reported.

Last week, two horses named Take Charge Briana and Wild on Ice were euthanized for "humane reasons" after they suffered injuries during training and race, Louisville Public Media reported.

Two other horses, Parents Pride and Chasing Artie, died under mysterious circumstances last week, after which their trainer Saffie Joseph Jr. was suspended indefinitely over "unexplained sudden deaths."

"Until we get some type of information it leaves you shattered, it leaves you broken," Joseph said, pointing out that he saw any of his horses collapse and die after a race until this week. "It's different when you have a horse get hurt as far as an injury, you have answers, you know what the cause was. When you don't know the cause that's the troublesome part, that's the nerve-wracking part."

Two additional horses, Chloe's Dream and Freezing Point, were also euthanized after they sustained severe injuries Saturday.

"Chloe's Dream in Race 2 and Freezing Point in Race 8 sustained racing injuries from which they could not recover on Saturday, and for humane reasons, both were euthanized," Darren Rogers, senior director of communications and media services for Churchill Downs told CNN. "The horses will be transported to the University of Kentucky Veterinary Diagnostics Lab for complete necropsies."

Officials at Churchill Downs termed each death as "unique," adding they noticed "no discernible pattern detected in the injuries sustained." Multiple authorities are partnering to investigate the unusual horse fatalities and ensure the safety of the animals.

"We will fully and actively work with the Kentucky Horseracing Commission and the Horseracing Integrity and Safety Authority to thoroughly investigate each incident to determine, to the degree possible, any underlying health or environmental causes and apply those learnings to continue to improve the safety of this sport," the statement added.

Horsemen are also struggling to find the causes behind the deteriorating condition of their animals.

Meanwhile, the University of Kentucky will conduct post-mortem examinations on the euthanized horses to determine the cause behind the crisis, said Kristin Voskuhl, a spokesperson for the Public Protection Cabinet which consists of the Kentucky Horse Racing Commission.

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AFP