A maintenance worker, who was also seriously injured, is credited with getting several people to safety just before the blast, which also destroyed 11 mobile homes.
Investigations continue into the Dec. 22 shooting of police Officer Timothy Hinton by the suspect, who later was shot by law enforcement officers in Canaan.
State Trooper Mickael Nunez, 30, was listed in serious condition Monday at MaineGeneral in Augusta. Police say Nunez was hit Sunday in China by a car driven by Robert Belmain, 53, of Caribou.
"We are hopeful. Our work will never stop. We will always continue. We've had several successes in the past with cases that are 10, 20 and 30 years old.” lead investigator Lt. Jeffrey Love said.