More than 3,000 people took part in a march organised by Youth Against Racism in Europe in protest at the killing of an 18- year-old black student, Stephen Lawrence, who was murdered by a white gang on 22 April in Eltham.
Violence broke out when people tried to break through barriers to attack a building used by the far right British National Party in Welling. Missiles were thrown and police on horseback charged the protesters to force them on past the building.
Fifteen demonstrators were taken to hospital, and two police officers were also injured. Although the demonstrators marched peacefully until they reached the BNP premises, the atmosphere was tense. Riot police moved in when some of the protesters tried to push away barricades in front of the building which was boarded up and apparently empty. Then missiles, including pieces of fence and wall from neighbouring gardens, were hurled. The BNP building was only slightly damaged.
In the fury, one white demonstrator was set upon by a group of black youths who thought he was a BNP member. He was beaten and kicked and had to be helped to safety.
Lynne Phillimore, whose garden wall was kicked down by demonstrators searching for missiles said: 'I think it is disgusting that the boy (Stephen Lawrence) was killed. But I can't see why they have to smash places up.
Commander Jim Gibson said: 'We are disgusted at the mindless violence that took place this afternoon.'
One of the organisers told the crowd at the end of the march: 'It was a marvellous show of strength.' She accused the police of being heavy-handed and called for all those arrested to be released immediately. 'There have been four racist murders in this area and young people are extremely angry.'
Earlier yesterday, three youths - two aged 17 and one 16 - were released on police bail after being questioned in connection with the murder of Stephen Lawrence.