VIOLENCE erupted again in the US city of St Louis today near the site of the police shooting of unarmed black teenager Michael Brown.

In the early hours, a police officer shot and critically wounded a man who drew a handgun near the site of protests over the killing.

And shortly after midnight, police fired tear gas at protesters who confronted a line of officers.

Officers were also fired on by one of four or five men with shotguns, police claimed.

The incidents followed two nights of protests in Ferguson, the largely black St Louis suburb where Mr Brown was shot.

President Barack Obama pleaded for calm and promised a full investigation by the Department of Justice.

“I know events of the past few days have prompted strong passions," he said.

“I urge everyone in Ferguson and across the country to remember this young man through reflection and understanding.”