WATERLOO, Iowa — Authorities are investigating whether heating equipment caused a large fire at the site of an amusement park being constructed in Waterloo.

Firefighters were called to the Lost Island Theme Park site, near the Isle Hotel and Casino, just before 8 p.m. Thursday. Crews found a 1,500 square-foot entrance shelter for one of the rides fully engulfed in flames.

Park owner Eric Bertch said it appears some temporary heating caught a blanket on fire.

The $100 million, 90-acre theme park being built adjacent to the Lost Island Water Park is tentatively scheduled to open in May or June. Bertch said the fire will not delay the park’s opening.

No one was injured in the fire.