The manhunt for shooting suspect Bradley William Stone has ended with the discovery of his dead body in the woods near his Pennsylvania home.

Stone, who was suspected of killing his ex-wife and five of her relatives and seriously wounding another in suburban Philadelphia, was a former Marine. According to Vince Lattanzio of NBC10 in Philadelphia, his body was located yards from his home, where SWAT teams have been methodically searching for the man.

"Law enforcement sources said it appears Stone killed himself," Lattanzio wrote. "Police also found a video recorded by Stone on a cell phone on or near his person, sources said."

NBC10 reported that prosecutors released an updated photo of Stone, a "selfie" retrieved from his personal cell phone, which was recovered along with his vehicle. The photo, which was taken in November, showed Stone wearing what looked like a green military jacket, red beard and a vacant expression on his face.

According to USA Today, authorities searched two days for Stone, 35, of Pennsburg, Pa., who police suspect shot and killed his ex-wife, Nicole Hill Stone. Both were in a dispute over who would get custody of their daughters, ages 5 and 7.

The other victims of the shooting rampage, according to NBC10, included Hill Stone's mother, grandmother, sister, brother-in-law and niece.

Montgomery County District Attorney Risa Vetri Ferman asserted at a press conference Tuesday morning that the authorities "will find Mr. Stone."

Hill Stone's nephew and the lone survivor of the shooting rampage, 17-year-old Anthony Flick, remained in serious but stable condition, according to Ferman.

"I cannot emphasize enough how serious his condition is, but at least at this point, we are hopeful that he will be fine," Ferman said.

According to USA Today, Stone served in the Marines and the Marine Reserves from 2002 to 2011, which included a 2008 combat tour in Iraq. He achieved the rank of sergeant, was honorably discharged, and won numerous awards and medals for his service.

Retired Navy Capt. William Nash, a psychiatrist, thinks that although the former Marine may have suffered from post-traumatic stress disorder, or PTSD, other stressors could have triggered his violent impulses.

"Another issue is if this Marine actually engaged in combat and if his job entailed killing people, then it could be that another mediator, another facilitator, another thing that may have made it easier for him to make these bad decisions is that he already has learned how to kill," Nash said. "And that's a whole other separate thing from having PTSD, it's a whole other separate thing from stress."

Nash added that "most people have an aversion to taking life." However, if that aversion is dulled for whatever reason, Nash noted that it would remove the "social obstacles" and contribute to "impulsivity."

According to Montgomery County records, Stone was treated for unspecified combat-related physical injuries. He also received continuing treatment for PTSD.

USA Today reported that Stone had previously been in trouble with the law before. He participated in a county rehabilitation program for veterans after pleading guilty in November 2013 to a drunken-driving crash.