A violent clash has broken out in Chicago’s predominately black South Side neighbourhood after police shot and killed a man they suspected was carrying a gun.

A crowd of about 150 residents shouted “murderers” and obscenities, local media reports said.

They tossed rocks, bottles and jumped on police cars as the protest escalated late on Saturday, local time, near the crime scene on 71st Street.

Officers armed with batons squared off with the protesters with punches thrown on both sides, multiple media accounts said and videos posted on Twitter show.

Officials said three or four officers suffered minor injuries, one patrol car was damaged and four protesters were arrested.

A reporter from the Chicago Sun Times, Nader Issa, was caught up in the protests, about which he tweeted.

Here's the start of the latest escalation, where Chicago Police rushed the protesters, who had been throwing bottles. More video to come. pic.twitter.com/EkSfzbcu4j

— Nader Issa (@NaderDIssa) July 15, 2018

Few details of the shooting were available other than a police statement, which said that about 5.30pm foot patrol officers saw a man “exhibiting the characteristics of an armed person”.

Fred Walker, patrol chief of the Chicago police, told the New York Times and other media, that officers saw a bulge in his trousers that they believed to be a gun.

When they approached the man, “He started flailing and swinging away, trying to make an escape” and he said the man “reached for the gun”.

The official statement from the Chicago police said, “an armed confrontation ensued resulting in an officer discharging his weapon and fatally striking the offender”, adding that they recovered a “gun and two ammunition magazines” at the scene.

We're at 71st & Jefferson in #Chicago responding to CPD killing another Black person. Here's what we know:
-CPD shot him in the back 7x
-IL is a conceal-carry state.
-a WW officer pulled the trigger
-This is the 2nd police killing in Chicago this month#StopTheCops #DefundCPD pic.twitter.com/MY13a1zD90

— BYP100 (@byp100) July 15, 2018

A crowd gathered after the shooting and rumours that the man was unarmed incited the crowd, police spokesman Anthony Guglielmi told the Chicago Tribune.

There has been a string of US police killings of black men that have sparked nationwide protests, but the name, age and race of the man shot were not released by police early on Sunday.

The protest ended about 10.30pm and the officer involved will be placed on desk duty while the incident is investigated, officials said.

-AAP