Municipals officials criticized the police yesterday for permitting an anti-black demonstration that flared into London's worst political violence in three years and left 110 persons injured.

Hundreds of leftists wielding fence posts and hurling bricks, bottles and smokebombs broke up a demonstration by the rightist National Front Saturday in the black South London neighborhood of Lewisham.

The rioters then turned on the police. Scotland Yard said 56 policemen were injured in a 35-minute battle.

Lewisham Mayor Roger Godsiff said, "I lay a lot of criticism for what happened at the door of [Scotland Yard chief] David McNee. We pleaded for him to recommend the home secretary ban the marches because we knew exactly what would happen and he refused."

But Home Secretary Merlyn Rees supported Scotland Yard's decision not to impose a ban.

In a radio interview, he said he deplored extremism of left and right, and added: "What we have to think about all the time even for people whom we despise, hate, disagree with - use what words you will - is the right for people to demonstrate in our sort of society."

He said that if Britain, which has a reputation for political tolerance, abandons that philsophy, "we might be moving along the road to where no marches can taken place at all."