CANADENSIS, Pa. — Nine days after a gunman went on a deadly ambush at a state police barracks, authorities said Sunday they have recovered one of the weapons he was carrying and believe they are hot on his trail as he travels on foot through rugged forests in northeastern Pennsylvania.

Investigators said they believe the suspect they describe as a self-taught survivalist had been planning a confrontation with law enforcement for months, if not years.

State Police Lt. Col. George Bivens revealed a few more details about the manhunt for Eric Frein, saying trackers have discovered items he hid or abandoned in the woods — including an AK-47 assault rifle and ammunition they believe he had been carrying while on the run.

“We are pushing him hard, he is no longer safe and I am confident that he will be apprehended,” Bivens said.

Authorities did not yet know if the weapon had been used in the ambush, he said. Still, police believe Frein remains dangerous and possibly armed with a .308 rifle with a scope that police say was missing from the family home along with the AK-47.

Since the Sept. 12 shooting, there have been no confirmed sightings of or contact with Frein, who was placed on the FBI’s Most Wanted list after the ambush at the Blooming Grove police barracks that killed Cpl. Bryon Dickson, 38, and critically wounded Trooper Alex Douglass.

The search is focusing on a several square-mile area on the border of Pike and Monroe counties around the nearby village where Frein grew up, Bivens said.

“We know that Frein has prepared and planned extensively for months, and maybe years,” Bivens said. “He planned his attack and his retreat.”

Bivens said Frein initially had the advantage of knowing the rugged terrain around the area.

“Our tactical operations people now also know his backyard, the area he once felt safe in,” Bivens said.

Heavily armed police and federal agents on Friday descended on the community of Canadensis where Frein, 31, had lived with his parents, ordering residents to stay inside and preventing anyone outside the neighborhood from returning to their homes. Law enforcement officers wearing bulletproof vests and armed with rifles scoured the woods as helicopters buzzed overhead.

Police ordered the lockdown, believing that Frein was close and there was the possibility of a confrontation, Bivens said. Now, they are telling residents to go about their normal lives but remain vigilant, keep their doors locked and stay out of the dense, boggy woods where the search is underway.