Skirmishes broke out between police and Muslim youths in North London last night as large crowds gathered to defend a mosque that had been targeted by anti-Islam campaigners.

Groups of youths, in ski masks and motorcycle helmets, threw bottles and set off fireworks in front of riot police, who used kettling tactics to contain a crowd of up to 2,000 outside Harrow central mosque. Seven people were arrested for possession of offensive weapons including a hammer, chisel and a bottle of bleach. Another man was arrested “to prevent a breach of the peace”, police said.

Hundreds of Muslim youths and anti-fascist campaigners gathered to confront a fringe right-wing group calling itself Stop Islamification of Europe (SIOE). The group had threatened to hold a rally at the site, where a new five-storey mosque is under construction, but organisers said that they had called off the march at the request of police.

Despite pleas by imams for the crowds to go home, the streets remained packed for several hours. About 20 anti-Islamic protesters, some wearing football jerseys, attempted to enter the area but were blocked by some of the 500 police.

Ajmal Masroor, a spokesman at the mosque, said: “People came here in the name of defending a mosque that does not need to be defended. We want the others to have their protest and we can ignore them.”

The unrest came after riots in Birmingham last weekend during an anti-Islamic rally by the English Defence League (EDL). There were dozens of arrests after clashes between the supporters of the right-wing league and Muslim activists.

The EDL, which also clashed with Muslim groups in Birmingham a few weeks ago, leading to 35 arrests, is affiliated to Casuals United, former football hooligans who want to “fight jihadists in the community”. The two groups are also affiliated with SIOE and they directed supporters to the Harrow protests from their Facebook pages and websites.

Of the anti-Islam supporters who attended yesterday, it was unclear with which group they were affiliated.

Police were continuing last night to contain two separate groups of anti-Islam protesters away from the road outside the mosque and there were still hundreds of anti-fascist supporters in the area.

In a statement, the police said: “Items, including bricks and bottles have been thrown at officers. Throughout the afternoon officers have had to be deployed in personal protective equipment, including the use of shields to prevent further acts of disorder.”

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