John Bacon and Michael Winter

USA TODAY

A survivalist who spoke of committing mass murder was the subject of an intense manhunt Tuesday, accused of fatally shooting a Pennsylvania state trooper in an ambush last week.

Authorities issued an arrest warrant for Eric Matthew Frein, 31, accused of first-degree murder in the killing of Cpl. Bryon Dickson II, a 38-year-old married father of two, at the Pike County barracks in Blooming Grove. Trooper Alex Douglass, 31, was wounded as he arrived for duty late Friday.

Both were in uniform and neither had a chance to return fire, which came from woods across from the station, state police said.

The sniper, using a high-powered .308-caliber rifle, also shot at a civilian dispatcher as she tried to aid Dickson at the front door but missed her. The gunman fired four shots over about a minute and a half, video surveillance indicates.

State Police Commissioner Frank Noonan said the attack Friday appeared to be aimed at law enforcement rather than the individuals he shot.

"He has made statements about wanting to kill law enforcement officers and commit mass acts of murder," Noonan said. "What his reasons are, we don't know. He seems to be very angry with a lot of things in society."

Lt. Col. George Bivens said at least 200 law enforcement officials were hunting for Frein, 31, who faces first-degree murder and other charges. Bivens described Frein as a survivalist, and Bivens warned that Frein should be considered armed and dangerous.

"I would encourage the public, if they see something suspicious, don't hesitate to call us," Bivens said.

Frein, of Canadensis, Pa., about 20 miles from the scene of the shooting, has only a minor criminal record, Bivens said.

The shooting took place in Blooming Grove Township, a town of 5,000 in a rural section of northeastern Pennsylvania about 35 miles east of Scranton. Noonan said a neighbor walking his dog found a Jeep Cherokee partially submerged in a swampy area about 2 miles from the site of the shooting.

Authorities then found Frein's driver's license, Social Security card and gaming permit, and two spent .308 shell casings, according to a state police affidavit. They also recovered two empty rifle cases, military gear, flashlights, a black hooded sweatshirt, camouflage face paint and "various information concerning foreign embassy's (sic)."

Investigators also found spent casings in the woods across from the barracks, and ballistics tests matched them to the casings found under the Jeep's front seat, police said. A search of Frein's home found 14 other spent cartridges that came from the same gun, along with a book titled Sniper Training and Employment.

Police said the gunman's rifle, which resembles an AK-47, is used by police and military sharpshooters and is popular with target shooters. Hunters also use a version of the rifle.

The affidavit said Frein's father is a retired U.S. Army major who served 28 years. He reportedly told investigators that he had trained his son in marksmanship, that his son was on his high school shooting team and that his son "doesn't miss."

Dickson was hit twice as he walked out the front door and Douglass once in the pelvic area, according to the affidavit. It did not indicate where Dickson was shot.

Communications operator Nicole Palmer said she heard a noise like a firecracker and then saw Dickson drop immediately. When she went to see what happened he told her he had been shot, and seconds later another shot whizzed past her and hit the lobby floor.

Palmer went back inside and called 911 but "was unsuccessful," the affidavit states, and she then returned to Dickson's side. She was unable to drag him inside and then went back inside for help.

Douglass was shot as he walked from the parking lot toward Dickson, and was brought inside by another trooper.

Dickson was pronounced dead at the scene, and Douglass was airlifted to Geisinger-Community Medical Center Hospital in Scranton.

Dickson was a Penn State graduate and a Marine veteran who joined the troopers in 2007. His funeral was set for Thursday at St. Peter's Cathedral in Scranton.

"It's gratifying to me that we could do this (name a suspect) before the funeral of Cpl. Dickson," Bivens said. Dickson's funeral is scheduled for Thursday.