BLOOMING GROVE, Pa. — Investigators returned Sunday to scour the woods across from a State Police barracks where two troopers were ambushed, leaving one fatally shot and another critically wounded.
Troopers also set up a checkpoint near the site where they were stopping motorists to ask whether they had seen anything that could help with the case.
A nonprofit group offered a $50,000 reward for tips about Friday’s deadly assault at the remote post in northeast Pennsylvania.
Reporters saw investigators walk into the dense forest surrounding the barracks in Blooming Grove around noon Sunday, though authorities suggested a day earlier that the suspect had already left the area. The barracks is about 35 miles from Scranton.
The troopers were ambushed around 10:50 p.m. Friday as one of them was leaving the barracks and another was arriving.
Corporal Bryon Dickson of Dunmore was killed and Trooper Alex Douglass was injured. Dickson, a seven-year veteran, had transferred to the region from the Philadelphia barracks several months ago.
Douglass was taken to a hospital and underwent surgery, and was in critical but stable condition.
State Police Commissioner Frank Noonan said the ‘‘cowardly attack’’ was directed at State Police and a ‘‘very dangerous, armed criminal’’ eluded quick capture.
‘‘Our troopers were . . . shot without warning and really had no chance to defend themselves,’’ Noonan told reporters Saturday afternoon. ‘‘It has touched us to the core that such a thing could happen.’’
Pennsylvania Crime Stoppers, which posted the reward offer, asked anyone with information to notify authorities.
Law enforcement officers from at least three states on Saturday searched state game lands surrounding the barracks in Pike County and beyond.
‘‘There has been an exhaustive search conducted by hundreds of members of law enforcement,’’ said Lieutenant Colonel George Bivens. ‘‘We have canvassed the wooded areas, neighborhoods. We are convinced this individual is no longer in that immediate area.’’
While they have not discussed a motive, authorities said there did not appear to be a threat to the public, although they said residents should be aware of their surroundings and report suspicious behavior.
Police interviewed a man they called a person of interest, but Noonan said authorities are talking to hundreds of people as part of the investigation. He stressed the man is not a suspect.
Dickson and his wife, Tiffany, had two sons.
‘‘They were a committed couple,’’ Melissa Contorno, a friend of Dickson’s wife, told The Times-Tribune of Scranton. ‘‘They were raising a beautiful young family. It’s not fair.’’