MONESSEN, Pa. — Three firefighters were transported to local hospitals after a house fire on Park Way in Monessen caused the floor to give out. One was sent by helicopter to the UPMC Burn Clinic and the two others were ferried by ambulance to Mon Valley. There is no word as to what initially started the fire. 911 officials said that they were alerted to the scene just before 3 p.m. on Saturday. The Monessen fire chief said when firefighters got to Park Way, another person came up and shouted that someone was inside. Firefighters went in to try to rescue whoever might be in there, while other firefighters worked to put the fire out. The fire chief said that when first responders went into the house, they confirmed that there were signs that a squatter had taken over. They didn’t find anyone in the house but the fire chief said a Charleroi firefighter fell through the second floor onto the first floor and had to be life-flighted. Two other firefighters were treated for heat-related issues.