The West Midlands police said Monday they have arrested six men in Birmingham at or near their homes, as part of a large anti-terrorism operation.

The men were arrested overnight on the suspicion of the preparation, instigation or commission of an act of terrorism, reported The Daily Telegraph.

The men, aged between 25 and 32, were detained by an unarmed policemen in the Moseley, Sparkbrook, Sparkhill, Ward End and Balsall Heath neighborhoods of Birmingham, said a police spokeswoman.

The spokeswoman also confirmed the arrest of a 22-year-old woman on Monday morning at 6:30 a.m., on the suspicion of failing to reveal information, under the Terrorism Act of 2000.

The arrests are not believed to be related to the Liberal Democrats' autumn conference, currently meeting at Birmingham's International Convention Centre. The suspects were taken to an unnamed police station in the West Midlands Police District for interrogation, said the spokeswoman, adding that specialist police are searching their homes and other properties in Birmingham.

Marcus Beale, assistant chief constable at the West Midlands Counter Terrorism Unit, said, "The operation is in its early stages so we are unable to go into detail at this time about the nature of the suspected offences."

She said, "I believe it was necessary to take action at this time in order to ensure public safety."

Anyone with information that may be useful for counter-terrorism investigations can call the confidential Anti-Terrorist Hotline on 0800 789 321.