61-year-old woman sitting on porch with her husband is gunned down after a long day working on their new food truck: Police

Inset: Shariff Perry (Philadelphia Police Department). Background: News footage of the porch where Michelle Wilson was fatally shot (WTXF).

A Pennsylvania man is still at large after police say he was responsible for opening fire on a couple while they sat on their porch.

Philadelphia police issued a warrant for the arrest of 35-year-old Shariff Perry in connection with the fatal shooting of 61-year-old Michelle Wilson on Aug. 9. According to reporting by local Fox affiliate WTXF, officers responded to calls about a man with a gun in a North Philadelphia neighborhood at 11:49 p.m. and found Wilson and her 67-year-old husband suffering from gunshot wounds.

Both Wilson and her husband were rushed to the hospital, where Wilson was pronounced dead minutes after midnight. Her husband remains hospitalized in stable condition.

Detectives asked for the public's help and shared surveillance videos of a man walking down the street, pulling a gun out of a bag and putting it in his coat. Another video from a different angle reportedly captured the same figure and flashes of gunfire. Police said they recovered around 20 shell casings that appeared to be from a handgun. News footage showed several bullet holes on the outside of the Wilsons' home.

On Wednesday, police identified Perry as their suspect and issued a warrant for his arrest for murder and weapons charges. Authorities are offering a $20,000 reward for information leading to Perry's arrest and conviction.

Police did not release a motive for why Perry allegedly killed Wilson or targeted the couple.

Aaron Lively, a neighbor who said he knew the Wilsons and grew up with them, told WTXF and local CBS affiliate KYW that the couple had just started a sandwich and taco truck business in the neighborhood. He told KYW, "They were good friends of mine. It's sad that it happened. They were hard-working people trying to make an honest dollar, selling their food. I grew up with them as kids. We all grew up together in the neighborhood."

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Anyone who believes they have information about where Perry can be located is asked to contact the Philadelphia Police Department's Homicide Unit at 215-686-3334 or call the tip line at 215-686-TIPS (8477). Tips can be submitted anonymously.