A Muslim cleric who is being investigated by the Home Office for alleged links to terrorism has defied a ban on speaking at a mosque in Cardiff.

Sheikh Omar Bakri Mohammed - the London-based leader of Al Muhajirounis - delivered his speech at a secret location in the city, following opposition from Muslim officials.

He is being monitored by police after expressing support for Osama Bin Laden.

He is also being investigated because of his militant pronouncements, which included a call for Britain to become an Islamic state.

Also, in the aftermath of September 11th, he imposed a fatwa on the Pakistani president.

Arrangements had been made for him to speak at Shah Jahal Mosque on Sunday, but mosque trustee Mohammed Ahad Chowdury blocked the move, saying the alleged extremist was not invited.

But BBC Wales understands that Sheikh Mohammed went ahead with his planned visit at a secret venue in the city.

His organisation was stopped from holding a meeting in Cardiff in the wake of the 11 September terrorist attacks in the US.

Sheikh Mohammed is understood to have regularly visited Cardiff to meet with students and has pledged that the banned visit this month will not put him off returning again.

We'll find out who gave the permission and we're going to take action against the person

Mohammed Ahad Chowdury

Mr Chowdury told BBC Wales: "At the moment, we don't know where they (Al Muhajiroun) got the permission from.

"We don't allow any sort of extremists: ourselves we are not extremist and there's no way can we allow those sort of meetings in our mosques."

"We are going to find out who those people are. As far as I know the majority of people in the community don't like extremists.

Mr Chowdury added: "Whoever gave the permission, it is totally wrong.

"We'll find out who gave the permission and we're going to take action against the person."

Speaking last week, Sheikh Mohammed said he could not understand why the ban had been imposed.