The Mansfield Fire Department and police are investigating a vacant house fire that happened late Monday afternoon on West Fourth Street. 
  
The fire started just before 5 p.m. at 548 W. Fourth St.
 

Asst. fire chief Chris Speelman said the fire started outside the rear of the house. He said the fire appeared suspicious.

Speelman said no one was injured in the fire.
 

Neighbors told police they saw a young boy playing with a paper towel that was on fire outside the house shortly before the fire started.