Investigators are looking into the origin and cause of a fire at the Charles County Fairgrounds that resulted in about $500,000 of damage, officials said.

Firefighters were alerted to the blaze at 3:25 p.m. Tuesday. The fire spread quickly, and it took about an hour and a half for roughly 170 firefighters from Southern Maryland, Virginia and the District to get the blaze under control, according to the Maryland State Fire Marshal's office.

The fairgrounds, located at 8440 Fairgrounds Road in La Plata, are leased to carnival workers during the winter months who reside in RVs while they perform in the area. Multiple renters were displaced and two dogs are dead because of the fire, officials said.

In addition to damaging several RV-style mobile homes being used by renters, the fire also damaged the fairgrounds' livestock show ring and attached barns. A statement from the Charles County Fair Board states that the group will be planning the process of rebuilding the damaged area.