LONDON: Police arrested dozens of people after protests across parts of England and Northern Ireland turned violent on Saturday, as the government pledged tough action against those it said were exploiting the murder of three girls to stir up disorder.

Violent protests involving hundreds of anti-immigration groups have erupted in towns and cities across Britain after three girls were killed in a knife attack at a children’s dance class in Southport in north-west England last week.

The murders were seized on by anti-immigrant and anti-Muslim groups as misinformation spread that the suspect was a radical Islamist migrant. Police have said the suspect was born in Britain. Media reports have said his family was Christian.

On Saturday, violent disorder broke out in cities around the country, including Liverpool, Bristol, Hull and Stoke-on-Trent, as well as the town of Blackpool, with local police saying they had arrested at least 87 people. There was also unrest in Manchester and Belfast.

Shops and businesses were vandalised and looted, a library in Liverpool was set on fire and several police were injured, police statements said.