Story highlights Frein claimed he shot two state troopers in bid to change government, documents say

His goal: to "wake up people, because it was all he could do," according to documents

Ambush left Cpl. Bryon Dickson dead and Trooper Alex T. Douglass wounded

Suspected cop killer Eric Frein was slapped with terrorism-related charges Thursday in Pennsylvania for allegedly admitting that he shot two state troopers in a bid to change the government and "wake people up," according to court documents.

The 31-year-old survivalist and military buff was captured October 30 at an abandoned airport after leading a small army of law enforcement officers on a weekslong manhunt in eastern Pennsylvania.

Frein was arraigned on charges including first-degree murder and making and possessing a weapon of mass destruction for pipe bombs found while he was on the run in connection with the September 12 ambush shooting that left Cpl. Bryon Dickson dead and Trooper Alex T. Douglass wounded.

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The manhunt lasted almost seven weeks, involved as many as 1,000 officers at times. Authorities said the search cost more than $11 million in salaries, travel, equipment, utilities and other expenses.

Prosecutors are seeking the death penalty.

On Thursday, Frein was charged with two terrorism counts for committing "a violent offense intending top influence the policy of the government by intimidation or coercion" and committing a violent offense "intending to affect the conduct of government," according to court documents.

After his arrest, Frein allegedly told investigators that he "wanted to make a change (in government) and that voting was insufficient to do so, because there was no one worth voting for," according to an affidavit filed in Pike County in support of the new charges.

Frein allegedly called the killing of Dickson an "assassination," the court documents said. The suspect said the shootings were an attempt to bring about a change in government and to "wake up people, because it was all he could do."

In addition, investigators recovered a letter from Frein to his parents -- addressed "Mom and Dad" -- on a thumb drive in which he writes of revolution and complains that the United States "is far from what it was and what it should be"

"I have seen so many depressing changes made in my time that I cannot imagine what it must be like for you," Frein allegedly wrote in the letter. "There is so much wrong and on so many levels only passing through the crucible of another revolution can get us back the liberties we once had. I do not pretend to know what that revolution will look like or even if it will be successful."

Frein's father, Michael, a retired U.S. Army major with 28 years of service, told investigators that he trained his son to shoot and that the younger Frein "doesn't miss."

"Tension is high at the moment and the time seems right for a spark to ignite a fire in the hearts of men," Frein wrote to his parents. "What I have done has not been done before and it felt like it was worth a try."

He added, "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."

Asked about the new charges, Frein's lawyer, Michael Weinstein, said: "These are just allegations right now, these are not substantiated yet. Let's take a look at this evidence. We'll take this one step at a time. These type of cases take a long time and require careful scrutiny."

Frein is charged in an ambush outside the state police barracks in Blooming Grove. Frein melted into the thick Pennsylvania woods after the shootings, authorities said.

After his arrest, authorities found a laptop, first aid supplies, shave kits, DVDs, contact lenses and even a copy of the New Testament belonging to Frein, according to police documents.

The suspect told authorities he used a Lenovo Thinkpad laptop while on the run to access open wireless connections and use the Internet, according to court documents.

Frein's trove of survival supplies indicated that he was well-equipped to survive alone in the wilderness for weeks or even months.

In addition to various articles of clothing and multiple weapons and ammunition, Frein had packed food items such as cup noodles, rice, beans, five-gallon water jugs, crackers, soy sauce, vegetable oil, and even a bottle of soju, a Korean vodka.

When he was captured, Frein did not put up a fight. He was shackled in the Dickson's handcuffs, put in the backseat of the slain trooper's squad car and driven to the barracks where the ambush on Dickson occurred.