Seven thoroughbred horses were killed Saturday when a fire roared through a barn at the Gulfstream Polo Club in Florida, a fire official said.

The barn was fully involved with flames when firefighters arrived shortly after noon, Capt. Albert Borroto of Palm Beach County Fire Rescue said in a statement. Seven thoroughbreds were killed and four were being treated for burns.

Fire Rescue Capt. Michael Bergeron told NBC 6 in Miami that the barn was 70 to 80 feet long.

“Not one inch of the barn was not totally engulfed in flames when I got there. The flames were 10 feet above the roof,” the polo club’s president, Randy Aversano, told The Palm Beach Post.

Investigators concluded that the fire was caused by an electrical fault in a tack room used as a kitchen, Borroto said.

No other structures were involved.

The club is in Lake Worth, south of Palm Beach.