FERGUSON, United States, Aug. 17 -- Clashes between police and protestors continued in this U.S. city in Missouri on Sunday as a curfew ordered by state Governor Jay Nixon is due to take effect for a second night.

Police fired at least 75 rounds of tear gas at a crowd of more than 5,000 protestors as they marched toward a police command post on Sunday night.

The protestors, who retreated shortly afterward 9 p.m., hurled Molotov cocktails towards police officers before the latter's firing of tear gas, St. Louis County police said.

Xinhua reporters at the scene did not see any injuries.

Unrest and violence have gripped the area for days since the recent shooting death of 18-year-old black young man Michael Brown by white police officer Darren Wilson.

The New York Times reported that Brown, who was unarmed, was shot at least six times.