A manhunt is underway in Pennsylvania to find 31-year-old Eric Matthew Frein -- the man police say is responsible for the ambush shooting on Friday, Sept. 12, 2014, outside of police barracks in Blooming Grove, PA that resulted in the death of one state trooper and another injured another. Police say Frein is "armed and extremely dangerous" and has "survivalist" skills, and has previously made statements about wanting to kill law enforcement officials and commit mass murders.
Possible sighting of suspected cop killer
01:27 - Source: CNN

Story highlights

Stains investigated for link to trooper shooting suspect Eric Frein don't pan out, police say

One stain was blood, but not Frein's; the other wasn't even blood

Frein is suspected in September 12 ambush of 2 officers, one of whom died

He may have been seen Friday night, police say

CNN  — 

Blood discovered during the search for Pennsylvania trooper shooting suspect Eric Matthew Frein is not his, state police said Monday.

Droplets of what appeared to be blood on the steps of a covered porch near the town of Cresco, Pennsylvania, turned out to be human, the Pennsylvania State Police said.

But DNA testing showed the blood wasn’t Frein’s, police said.

Material found on the inside of a screen porch door at a nearby home wasn’t blood at all, police said.

Neither has any link to the search for Frein, according to police.

Police read excerpts of notes they say suspect left

On Friday, a law enforcement source speaking on condition of anonymity told CNN that there was no reason to believe that Frein was injured or that the blood was Frein’s.

Frein, 31, is suspected in the September 12 ambush shooting that left Cpl. Bryon Dickson dead and Trooper Alex T. Douglass wounded outside the Pennsylvania State Police barracks in Blooming Grove in northeast Pennsylvania.

Police have not spoken about a possible motive, other than that Frein has talked and written about hating law enforcement. Authorities have said that a review of a computer hard drive used by Frein shows that he had planned the attack.

Police: Suspect planned ambush for months

He has eluded escape despite a massive police search around Canadensis, Pennsylvania, where his family has a home.

Police say they think a woman taking a walk Friday night saw Frein, armed with a rifle and his face dabbed with mud, in a wooded area near the eastern Pennsylvania town of Swiftwater, about 8 miles southeast of the Canadensis area.

CNN’s Jason Hanna, Shimon Prokupecz and Ray Sanchez contributed to this report.