The lone suspect in an ambush shooting that killed one Pennsylvania state trooper and injured another texted his friend hours before he allegedly opened fire, according to a published report. 

The Scranton (Pa.) Times-Tribune, citing a search warrant affidavit, reported that Eric Frein texted his longtime friend Justin Smith with a message that read, in part "all is good."

The text, which was received at around 6:15 p.m. on the night of Sept. 12, went on to say that Frein had spent the night at Smith's apartment in East Stroudsburg and had met the latter man's aunt. Frein also said that he was "heading to Delaware" and would return the following week. 

Later that night, police believe, Frein, 31, fatally shot Cpl. Bryon K. Dickson II and wounded Trooper Alex T. Douglass outside the state police barracks in Blooming Grove, Pa. Frein remains at large three weeks later, though police believe that he is hiding somewhere in the woods near his childhood hometown of Canadensis, Pa. Police have also said Frein lied to relatives and other people that he was working in Delaware so he could prepare for the ambush.

Smith's apartment was searched by police three days after the shooting, according to the paper. Among the items recovered were several boxes of ammunition and 10 dirty gun cleaning patches. When interviewed, Smith told police that he last saw Frein on Sept. 1, when Smith left to work on a military film in Virginia. The Times-Tribune reported that Smith described himself to police as Frein's "only friend." The two had known each other since they were teenagers and were both passionate about military reenactments. The two were so close, in fact, that Smith told police that Frein had a key to his apartment. 

Smith has not been charged in the ambush and authorities believe that Frein acted alone. 

The manhunt entered its fourth week Saturday. Authorities said Friday they have found caches of supplies in the rugged, heavily wooded search area. Tuna fish, ramen noodles and other food was recovered along with clothing and 90 rounds of ammunition from a campsite where police previously said they found two pipe bombs, according to investigators.

The Associated Press contributed to this report. 

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