Scotland Yard probes threats against the pope

London, England - Scotland Yard has launched an investigation into a London protest at which calls were reportedly made for Pope Benedict XVI to be "subject to capital punishment" for his controversial remarks about Islam.

Scotland Yard Assistant Commissioner Tarique Ghaffur said on Monday that the force had received "a number of complaints" about the reported comments by a leading Muslim extremist at a protest in London on Sunday.

Many of the complaints related to alleged comments made by Anjem Choudary, who has been described as a former leader of the outlawed Al-Mujaharoun group.

"Anyone who insults the message of Mohammed is going to be subject to capital punishment," Choudray told the gathering, press reports said on Monday.

British police were "facilitating lawful demonstrations", but will not allow people to break the law at demonstrations, Ghaffur said in a statement on Monday.

Police were investigating what took place at the protest outside Westminster Cathedral, London's main Catholic church. About 100 people protested outside as worshippers left mass on Sunday morning.

They said they would also examine other publicly made statements, with a view to ascertain if any criminal offences had been committed, Ghaffur said.

"We will always proportionately police all protests but equally will take decisive action where crime is committed," he said.