Matthew James Branning, 50, of Sellersville, and Michael Allen Stark, 47, of Royersford, worked together at Enchlor, Inc. in Silverdale Borough.
One day in October, both stopped showing up for work, Bucks County District Attorney Matt Weintraub said.
"I don't believe in coincidence," Weintraub told NBC10. "So candidly, we suspect foul play. Nobody quit the job. They just stopped appearing. It's like they ceased to exist."
Branning was last seen Oct. 15, and Stark on Nov. 13, at a pawn shop in Michigan, authorities said.
Branning’s car, a 2002 Lexus SUV, with PA Registration KWS-5619, has also not been found, authorities said.
Stark is considered a person of interest in Branning’s disappearance, District Attorney Matt Weintraub said.
Branning was last seen leaving his job on Oct. 15, and was captured surveillance video driving up to an ATM in Sellersville at 4 p.m., authorities said. In the video, a person is partially visible, but unidentifiable, in the back seat of his vehicle.
The 2002 Lexus SUV was then seen traveling into Central New Jersey around 5 p.m., then south into Cape May, the DA's office said.
Investigators were able to trace Branning's cellphone to a Wawa in Cape May at at 9:08 p.m. Wawa surveillance video shows Stark making a purchase at 9:24 p.m., but Branning is not seen in the video, Weintraub said.
Following that, toll information shows Branning's Lexus traveling northbound and then westbound on the Atlantic City Expressway. There has been no activity on Branning's cellphone, bank account, or contact with his family since that date, authorities said.
Investigators say every attempt to locate his vehicle has yielded no results.
According to his family, there is no explanation for Branning's unexpected trip to New Jersey, and it is out of character for him to not contact his family or miss work, where he had been employed for nine years, Weintraub said.
All attempts by family, friends, coworkers, and law enforcement were unsuccessful until Nov. 13, when Stark was positively identified on video at a pawn shop in Garden City, Michigan, authorities said.
Anyone with information is urged to contact Bucks County Detectives at 215-348-6056, or Detectives with the Perkasie Police Department at 215-257-6876.
They can also anonymously contact the Pennsylvania Crime Stoppers toll-free number at 1-800-4PA-TIPS (8477) or online at https://www.p3tips.com/tipform.aspx?ID=107. All callers to Pennsylvania Crime Stoppers could be eligible for a cash reward.
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