MILFORD, Pa. — A judge Monday ordered a survivalist who called for revolution to stand trial on charges he fatally shot a Pennsylvania state trooper and wounded another outside their barracks.

The ruling came after a preliminary hearing for Eric Frein, 31, who is charged with first-degree murder and related offenses in the Sept. 12 ambush that killed Cpl. Bryon Dickson and critically wounded Trooper Alex Douglass.

Investigators testified that they found the murder weapon along with a journal in which Frein described shooting the troopers.

After the hearing, a defense lawyer, Bill Ruzzo, said his primary goal is to save Frein’s life. Prosecutors are seeking the death penalty.

In court, Pike County prosecutors showed surveillance video of Dickson crumpling to the ground after being shot, followed by Douglass, who had knelt beside his mortally wounded comrade.

Douglass then crawled into the lobby of the Blooming Grove barracks on his stomach – his legs immobilized by the gunfire – where a trooper dragged him through a doorway and out of sight.

After the ambush, Frein led authorities on a 48-day manhunt through the heavily wooded Pocono Mountains before U.S. marshals captured him at an abandoned airplane hangar.

A trooper testified Monday that bullets from the shooting scene were fired from Frein’s rifle, which was recovered at the hangar.

Authorities say Frein confessed to what he described as an assassination designed to “wake people up.”

They say he also wrote a letter to his parents – the text of which was read in court Monday – calling for revolution to “get us back the liberties we once had.”

“I do not have a death wish but I know the odds. I tried my best to do this thing without getting identified, but if you are reading this then I was not successful,” said the letter, found on a computer storage drive that prosecutors say Frein had with him while he was on the run.

Frein was shackled with Dickson’s handcuffs and driven to the police station in Dickson’s squad car. Dickson’s widow attended the hearing.