Atlanta police are investigating four shootings overnight Wednesday that resulted in the death of one man and injuries to three other people.

Shortly after 10 p.m. Wednesday, officers responding to a report of a person shot outside a Moreland Avenue grocery store found a man with a gunshot wound to the head. Despite efforts by emergency crews to save him, he died from his injuries, police said.

The victim’s identity has not been released.

Also Wednesday, a man working as a security guard at a complex on Woodland Avenue was shot in the leg after apparently chasing two men he had recognized from a previous incident, according to preliminary information from police.

The victim, Demetric Howard, 26, was taken to Grady Hospital, where he was reported to be in stable condition Thursday morning. Howard told police that he returned fire at the men and was unsure if he had struck them.

Early Thursday, another man was shot in what officers were told was a dispute with a neighbor at their rooming house on Lakewood Avenue.

The victim, identified by police as Williams Robinson, 36, suffered a gunshot wound to the hand, as well as several stab wounds to the back. Police said Robinson would not say what had happened or who shot him. However, police said the victim’s wife told them he was shot during a dispute with a neighbor at their rooming house. The neighbor fled, she said.

Around 1:30 a.m. Thursday, police were called to Grady Hospital after a woman was dropped off there with a gunshot wound to the back. A friend who took her to the hospital reported told police their vehicle had been hit by gunfire after they had been with an acquaintance in the 1500 block of Martin Luther King Jr. Drive.

The victim, whom police did not identify, was reported on Thursday morning to be in critical but stable condition.