At least four people were killed and 18 injured in a mass shooting in Birmingham, Alabama, according to police.

“Multiple gunmen fired multiple shots at a group of people in the Five Points South neighborhood late Saturday,” said Birmingham police Officer Truman Fitzgerald.

Officers found the bodies of two men and a woman at the scene, while a third man later died of gunshot wounds in hospital, Birmingham police said.

Investigators are looking into whether the shooters approached the victims or drove past them, Fitzgerald said. No suspects have been arrested.

He added that it was believed the shooting “was not random but was an isolated incident in which several victims were caught in the crossfire.”

Investigators are working to determine who the intended target or targets of the attack were, Mr Fitzgerald also said.

The Five Points South district is known for its nightlife. The shooting occurred on Magnolia Avenue, Mr. Fitzgerald said.

Witnesses who were queuing outside a hookah and cigar lounge on Magnolia Avenue at the time told local news site Al.com that some of the shots sounded like they came from a rifle that had been converted to a fully automatic rifle.

Mr Fitzgerald had previously told reporters after the incident that there were “dozens of gunshot victims”.

According to the Gun Violence Archive, It defines a mass murder as an incident in which four or more people are injured or killed.