LOUISVILLE, Kentucky: Two horses that succumbed to their injuries at Churchill Downs have become the 11th and 12th fatalities over the past month at the home of the Kentucky Derby.

While mare Kimberley Dream was euthanized after sustaining a rupture to her front leg, Lost in Limbo was euthanized following a similar injury just before the finish line in a May 26th race.

The track stated that both injuries were "inoperable and unrecoverable."

"We do not accept this as suitable or tolerable and share the frustrations of the public, and in some cases, the questions to which we do not yet have answers," the statement added. "We have been rigorously working, since the opening of the meet, to understand what has led to this spike and have yet to find a conclusive discernible pattern, as we await the findings of ongoing investigations into those injuries and fatalities."

Also, a Kentucky steward's report from May 13 lists the previously unreported death of Bosque Redondo, after finishing 10th in a May 26 race.

An epidemiological study with the Jockey Club is reviewing each horse to determine undetected patterns not previously identified, the statement added.

"We are troubled by this recent string of fatalities," the statement said. "It is extremely inconsistent with the outcomes we have experienced over the years, with the reputation we have developed over the decades and with the expectations we set for ourselves and owe our fans. We are committed to doing this important work and updating the public with our developments."

Seven horses died at Churchill Downs from training or racing injuries in the week leading up to the 149th Kentucky Derby on May 6, starting with qualifier Wild On Ice on April 27. Two were euthanized following injuries on the Derby undercard, less important races, and two others died on May 14 and May 20.