Dallas gunman shot dead by sniper

US authorities have confirmed the death of a suspect accused of opening fire on officers outside the Dallas police headquarters.

Police said that the suspect was found dead inside his armoured van at a car park in suburban Hutchins, where he had been in an hours-long stand off with Swat team officers.

Police chief David Brown said a sniper hit the suspect shortly after 5am and that officers had lost contact with him for several hours. But officers did not directly approach the van due to the threat of explosives inside.

Witnesses said the suspect fired several rounds at officers and rammed his van into a squad car before fleeing.

No one was injured in the gunfire.