A number of protesters clashed with police in Hong Kong's Central district early Monday.
At about 7:20 a.m. local time, police charged towards protesters who had camped out on the street since 4 a.m.
According to a statement released by police, protesters have gathered iron poles, bricks from a nearby construction site and guard rails to barricade a road and obstruct traffic.
Local TV station HKiCable broadcast live video of riot police and protesters surging towards each other, with police holding batons and demonstrators using umbrellas in the clash.
"Police strongly condemn these illegal acts and warn protesters not to throw bricks or charge police cordon lines. Police appeal to protesters not to resort to violence, stop blocking roads and leave the scene as soon as possible," according to a police statement.
July 1 is the 22nd anniversary of the handover of Hong Kong from British rule to China. The day is usually marked with protests, but not in such a violent and tense fashion.