A man delivering a pizza was slain Sunday night in the Seat Pleasant area of Prince George’s County, and a second man was shot and killed in a separate incident at a Capitol Heights gas station, county police said. A third non-fatal shooting was reported overnight in Capitol Heights as well.

Around 8:30 p.m., the Domino’s delivery man was found lying on the ground with a gunshot wound in the 8600 block of Seat Pleasant Drive, a street in a residential neighborhood of modest apartments and single-family houses.

Cpl. Mike Rodriguez, a spokesman for the Prince George’s County Police Department, said the man was taken to a hospital, where he was later pronounced dead.

Police are still looking for a motive in the killing, but said that robbery was among those being considered. No arrests had been made in connection with the slaying as of early Monday, and police had not released the identity of the victim.

On Sunday night, someone who answered the phone at the Domino’s restaurant on Central Avenue, about a mile from where the man was found, said detectives were there, speaking with the store manager. However, the store employee said he had been given no information about what happened. A law enforcement source said it appeared that the slain delivery man had been shot in the chest.

The second killing occurred at the Shell gas station near the intersection of Central Avenue and Ritchie Road in Capitol Heights, Rodriguez said. A man was shot and killed around 3:20 a.m.

The circumstances of the shooting were not immediately available, but Rodriguez said witnesses were being interviewed by police.

Police are also exploring whether the shooting may have involved a group of people leaving a nearby club, Rodriguez said. He didn’t elaborate.

In a third incident, police were called to a non-fatal shooting in the 6900 block of Walker Mill Road in Capitol Heights shortly after 5:40 a.m. Cpl. Erica Johnson said it was an apparent robbery. The victim was transferred to the hospital and is recovering. Police said there is no indication at this time that the shooting is related to the other killings.

The killings were the third and fourth in the county since Thursday. There was no indication of any connection among them.

Two of the homicides occurred Thursday, and suspects were arrested in both.