The Charity Commission told the Guardian it was also examining another mosque in Cardiff – the Al Manar mosque, where the three men who travelled to Syria worshipped. Nasser Muthana, Assel Muthana and Reyaad Khan from the city travelled to Syria last year. Nasser Muthana subsequently appeared in a propaganda video produced by Isis. It is thought up to six men from the Welsh city may be in Syria.

Sheikh Zane Abdo, imam of the South Wales Islamic centre in Butetown, said many were concerned about speakers with extremist links preaching in Cardiff. “The local Muslim community, the mosques, our leaders need to be working a lot more closely with each other and with the local authority, with the parents, with the police to prevent people from being radicalised, to prevent further heartache,” he said.

In Birmingham a leaked police report published this week reveals that extremists are providing support and facilitation for those wishing up travel abroad to fight. The report, written by former assistant chief constable Sharon Rowe in 2013 and leaked to a local newspaper on Friday, says: “Influential extremists continue to operate in Birmingham, promoting extremist ideologies.” Rowe said they were operating from locations including gyms, restaurants and cafes, which are “used to facilitate extremist activity by allowing key figures to operate and promulgate their message”.