British officials alarmed by a reported plot to kidnap and murder a British Muslim soldier may strengthen security to protect Muslims in the police and armed forces, news reports said Friday.

The fears stemmed from the arrest of nine men in Birmingham on Wednesday. Media reports claim the men were plotting to kidnap a British Muslim soldier, torture and behead him, and broadcast the footage on the Internet — but this has not been confirmed by police.

A judge on Thursday gave police permission to question the suspects for seven more days.

On Friday, David Shaw, the West Midlands police officer in charge of the investigation, told a news conference that a "significant quantity" of exhibits had been collected by officers searching 18 properties involved in the alleged Birmingham kidnap terror plot, including three buildings searched Friday. He declined to identify the exhibits.

The nine suspects, believed to be British men of Pakistani descent, were arrested in homes and businesses in several Birmingham neighborhoods and were to be questioned Friday.

The Guardian newspaper said the Association of Muslim Police Officers had raised concerns with London's Metropolitan Police.

"We are aware that uniformed Muslim police officers have been confronted by Islamic extremists and threatened," said Superintendent Del Babu, chairman of the Muslim Police Association.

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Last year a Muslim officer asked to be moved from guarding the Israeli embassy because of a concern for the safety of his family in Lebanon if he were seen on duty at the embassy at the time when Israeli armed forces were pounding Lebanon.

The Times, quoting unidentified sources, said the Ministry of Defense was considering whether further steps were required to protect some 330 Muslims in the armed forces and their families. The newspaper said defense officials were alarmed by a report that names and addresses of 25 serving Muslims were discovered in the raids in Birmingham.

West Midlands police declined to comment on the report.

New guidelines on personal safety were expected to be issued to those people within a few days, The Times reported.

The Ministry of Defense declined to comment on that report.

The Sun, meanwhile, quoted unidentified sources as saying that two Muslim soldiers cooperated with police, acting as bait to the alleged plotters.

One of the men arrested helped work on the campaign to free Norman Kember, a British hostage kidnapped in Iraq in 2005 and held for 118 days, according to former Guantanamo Bay detainee, Moazamm Begg, who drafted letters and appeared on television pleading for Kember's release.

Kember was part of a Canada-based group, Christian Peacemaker Teams. The kidnappers shot dead an American member, Tom Fox.

"One of the men arrested actually helped draft my statement to release Kember," Begg told The Associated Press. "There is an enormous amount of skepticism over these arrests, and I think one of the problems is that there is still a huge intelligence gap."

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