The warning comes as police forces across the country stepped up patrols outside mosques today in the light of the attack in New Zealand where 49 people were killed at two mosques.
The country’s police commissioner, Mike Bush, said 49 people were confirmed dead and that a man in his late 20s had been charged with murder.
Mohammed Kozbar, who is also general secretary of the Finsbury Park Mosque where one man was killed in an attack in June 2017, said the New Zealand mosque attacker “just wanted to send a message that anyone can do that, that the Muslim community are not safe, and they can kill them whenever they want”.
“This has to be taken very seriously by the authorities and secure the safety of our people,” he said.
Speaking at Finsbury Park Mosque in north London, where people left flowers outside remembering the attack of two years ago, Mr Kozbar said: “It is shocking and beyond imagination.
“Innocent people being massacred in that way while they’re going to pray is something which shocked everybody. Our message is we are a resilient community and we will not be intimidated by this. This is what our community is about, solidarity and community. We will make sure these people will not succeed, whether it’s this perpetrator or other far-right extremists here in the UK or elsewhere.”
Meanwhile, a service was held at the Leeds Grand Mosque in the city earlier this afternoon.
Hundreds of Muslims came together in a stand of unity in Friday prayer that reduced many to tears as they sat with their own families including young children.
Sheikh Taher told the congregation: “We woke to the devastating news of what happened to our brothers and sisters in Christchurch and how innocent men. women and children were killed for no reason.
“The hand of crime, the hand of evil, the hand of terror has no religion, has no colour, has no race and this is a hand which is cut off from Allah.
“It is a sinful hand driven by hate, jealousy and anger.”
He urged the community to show patience and gratitude in testing times and trials adding: “This is what our religion teaches us - that these trials and tests come our way and we show patience, our beliefs remain firm and do not allow a calamity to shake you or your beliefs.” He then asked the community to stay behind for the Janazah prayer. It does not form part of the usual service but the Islamic funeral prayer was read especially for the victims.
West Yorkshire Police Temporary Chief Constable John Robins said officers had a presence around religious buildings and the force stood strong with Muslim communities.
Mr Robins said: “We stand together with our Muslim communities and all those shocked and horrified by this terrorist attack in New Zealand.
“The tragic events demonstrate attacks can occur at any time and without warning. There is no new increased threat to West Yorkshire. The UK threat level remains at severe meaning an attack is highly likely. We are stepping up reassurance patrols around places of worship and increasing engagement with communities of all faiths.
“We are committed to keeping the people of West Yorkshire safe and will continue to review the situation in regular liaison with our partner agencies to ensure we are doing everything we can around the clock to allow people to go about their daily lives.”
Home Secretary Sajid Javid is set to have talks with anti-terrorism chiefs and security officials to discuss possible further measures to protect mosques in the UK.