A robber shot and killed a worker at a Germantown bar early Thursday during a stickup at closing time, police said.

The suspect had been drinking at the DelMar Lounge on the 300 block of West Chelten Avenue and waited until the other patrons left before pulling out a gun and announcing a robbery shortly after 2 a.m., police said.

At an afternoon news conference, Homicide Capt. Jason Smith said surveillance video showed the gunman, whom police had not yet identified, firing one shot at the chest of 58-year-old bar worker Jeffrey Johnson after Johnson briefly hesitated when responding to the gunman’s commands. Smith said the robber then stole about $200 from a witness and left. He was last seen running eastbound on Chelten and then south on Pulaski Avenue.

Johnson was taken to Einstein Medical Center, where he was pronounced dead at 2:30 a.m. Smith said Johnson had “presented no threat” to the gunman.

Police released video that showed the gunman entering the bar, pointing his weapon, and walking away after the shooting.

Earlier Thursday, Chief Inspector Scott Small told reporters that the suspect left behind fingerprints and possible DNA evidence on the glass from which he was drinking. Smith declined to comment on evidence investigators were examining.

As with all homicides in the city, a $20,000 reward is being offered for information leading to the arrest and conviction of the criminal.