After the slaying last month, Randolph Sanders told a television station that he was "stunned" by the death of 56-year-old Kim Jones, a mother of two.
"She was incredibly happy," Sanders said in the interview with WPVI-TV in Philadelphia. "So this is — this is just disturbing."
But over the weekend, authorities say, he confessed to shooting Jones once in the back of the head in what homicide Capt. James Clark described as "a premeditated assassination-style" killing.
Jones suspected Sanders was stealing from Turning Points for Children, and Sanders was worried he might lose his job. Fearing Jones would report him, Sanders stalked her for more than an hour before shooting her at the bus stop Jan. 13, Clark said.
Police don't know why Sanders might have stolen, and he didn't say why in his confession, Clark said.
Sanders, of Philadelphia, was arraigned early Monday on murder and firearms charges and ordered held without bail pending a Feb. 18 preliminary hearing. His court-appointed attorney declined to comment Monday night.
Clark said detectives worked around the clock for two weeks reviewing hundreds of hours of surveillance video. They were able to track the suspect from the bus stop to a vehicle 3 miles away and got their break when they discovered Sanders drove the same kind of vehicle, Clark said. They brought him in for questioning Saturday, and that's when he confessed, authorities said.
"This is the type of investigation that leaves you both angry and confounded," Deputy Commissioner Richard Ross said. "It just breaks your heart."
Wesley Hatton, Jones' next-door neighbour, said Monday that he's known her family since they first moved to the neighbourhood more than 50 years ago. Hatton, who said he helped teach Jones how to ride a bike, said he couldn't imagine how someone could hurt her.
"She always had a smile on her face," Hatton said. "I never saw the girl mad. How did she have any enemies?"
Jones moved back to the house in recent years and would walk to the bus stop every day to get to work, Hatton said.
Sanders, who had no previous police record, was not a suspect initially and even called Jones' house after the slaying to check on her, Clark said. The two had clashed before, but investigators had no reason to suspect he would have killed her, police said.
"He killed her because he was stealing, she found out about it and he knew she was going to turn him in," Clark said of Sanders, who worked under Jones for more than two years.