Sampson was a certified therapy dog for his owner. (Longmont Fire, Police, OEM)

Sampson the dog was already having a tough day. His owner, 59-year-old Robert Corbey, had suffered a seizure and fell while taking him on a walk. But then, as emergency responders treated the man in the parking lot of a 7-Eleven, a woman arrived and took him away.

Police in Longmont, Colo., say that Sampson was taken as his master lay dying. In a Facebook post, police said surveillance video captured the incident, which showed the woman pulling the dog away from the scene on Tuesday evening.

On Thursday, police announced their suspect: 30-year-old Melody Mellon, who had several outstanding warrants.

For a long time, nobody knew where Sampson had gone, and his disappearance added more grief to an already tragic day. Corbey died after being transported to a hospital, the Longmont Times-Call reported, and his family “not only lost a treasured family member, but are also missing his companion,” Longmont police wrote on Wednesday.

As his owner died, Sampson was nowhere to be found. Police asked the public to help find him.

On Wednesday afternoon, Longmont Deputy Jeffrey M. Satur spotted a couple walking with a very familiar-looking dog.

“I was like, ‘Oh, there he is!’ I recognized him right away,” Satur told CBS4.

A woman had handed Sampson to the couple, according to Satur. They’d given him a bath and some crackers.

“They knew the dog was missing,” Satur said. “They were like, ‘Here, take the dog.' ”

Satur told the Washington Post that police identified Mellon as a suspect based on a photo and statements made as she was arrested for allegedly stealing a car in the early hours of Thursday morning.

Just after 4 a.m., a Longmont police officer responded to a call over a missing vehicle, according to a police report. Mellon was later discovered passed out in the vehicle, and became combative when police arrested her. She was taken to a local hospital for medical clearance, and was cleared for incarceration.

Mellon was arrested on several outstanding warrants, including assaulting a police officer, resisting arrest and auto theft, and was taken to the Boulder County Jail, according to Satur. She has been summoned to appear in court in November for a charge related to stealing Sampson.

On Wednesday, Sampson received a warm homecoming from a large group of family members, which included “kisses all around,” Longmont police said on Facebook. But one person in Sampson’s life was notably missing: Corbey, for whom he had served as a certified therapy dog.

But for the family, having Sampson was comforting.

Kelly Pleffner, Corbey’s niece, told CBS4, “It feels like we have a piece of my uncle, having Sampson back.”

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