A fire has ripped through a barn at a county fairgrounds in southwest Ohio, killing two people and dozens of horses.

The fire was reported about 5 a.m. Saturday. Capt. Krista Wyatt of the Lebanon Fire Department said the barn roof had already collapsed by the time firefighters arrived at the Warren County Fairgrounds, about 25 miles northeast of Cincinnati.

The victims' identities were not immediately released. Authorities initially thought up to 60 horses were dead. The latest number came to 43.

Lamar Moody, lead trainer at Lebanon Raceway, a harness racing track based at the fairgrounds, said two of his employees were not accounted for.

The cause of the fire was not known. Investigators were going through the rubble. The barn is about the length of a football field.