Four people have died and more than 20 were wounded in a shooting in a nightlife area in Birmingham, Alabama, according to police and news reports.

The violence is just the latest shocking incident that highlights the epidemic of gun violence and killings that continues to plague the US and yet prompts little to no political action.

Police said say multiple victims in the mass killing were caught in crossfire and offered a reward for information leading to the arrest of those involved.

There were multiple people shot on 20th Street near Magnolia Avenue in the Five Points South area, the Birmingham police department said in a social media post.

The shooting happened shortly after 11pm on Saturday in the city’s Five Points South entertainment district, the officer Truman Fitzgerald said in an email.

Officers arriving at the scene found two men and a woman on a sidewalk with gunshot wounds, and they were pronounced dead there. An additional male gunshot victim was pronounced dead at a hospital, Fitzgerald said.

A preliminary investigation showed that “multiple suspects fired upon a large group of people who were outside in a public area”, Fitzgerald said.

“Detectives believe the shooting was not random and stemmed from an isolated incident where multiple victims were caught in the crossfire,” Fitzgerald said.

Injured people began showing up at hospitals, Fitzgerald said. By early Sunday, police had identified 18 other victims with injuries, some of them life-threatening.

Some victims were transported to hospitals in private vehicles, police told WBMA.

The Five Points South area of Birmingham has numerous entertainment venues, restaurants and bars and often is crowded on Saturday nights.

Police said there were no immediate arrests.

“We will do everything we possibly can to make sure we uncover, identify and hunt down whoever is responsible for preying on our people this morning,” Fitzgerald told WBMA.

The US has a high rate of mass shootings, which frequently prompts public calls for more substantial gun control. But the US federal government has generally been unwilling or unable to heed those calls.

The gun rights lobby remains strong in the US and its power over politicians who try to enforce tighter gun laws is formidable.

In June the conservative-dominated supreme court struck down a federal ban on “bump stocks”, accessories which can allow a semiautomatic gun to fire as fast as a machine gun. Following the 6-3 decision Joe Biden condemned the ruling, saying it “strikes down an important gun safety regulation”.