LONDON (AP) - One of seven people arrested over an alleged plot to launch a terrorist attack in Britain has been released without charge, police said Sunday, as detectives continued to question more than a dozen other people over two alleged plots.
The Metropolitan Police said the 30-year-old woman detained in London on Thursday has been freed.
Five men and a woman are still being questioned over allegations of "the commission, preparation or instigation of acts of terrorism."
The suspects include a British Muslim convert who once appeared in a documentary about Islamist extremism and three brothers who were detained by armed police at their home near London's Olympic Park.
Counter-terror officers are on high alert ahead of the Olympics, which begin July 27, but police say the arrests are not connected to the Summer Games.
They are among a spate of pre-Olympics arrests and security scares.
The Sunday Telegraph newspaper reported that a terrorist suspect who is subject to limits on his movements under a contentious order known as a Terrorism Prevention and Investigation Measure was arrested in May after traveling by train five times to Stratford railway station, beside the Olympic Park.
The man, suspected of ties to Somalia's al-Shabaab militants and identified in court documents as CF, did not enter the Olympic venue.
Separately, police in central England are questioning seven men arrested after a car stopped by police on a highway for being uninsured was found to contain guns, ammunition and other weapons. Police have not given full details of the haul but say the guns were not automatic and were not loaded.
On Thursday, armed police closed a highway in central England, evacuated dozens of passengers from a bus and sent in bomb disposal units after a passenger reported vapor coming from a bag. The source turned out to be an electronic cigarette, designed to help smokers quit.
Britain's terrorist threat risk remains at substantial, the middle point on a five-point scale, meaning an attack is a strong possibility. Intelligence officials say there has been an expected increase in chatter among extremist groups ahead of the Olympics, but there are no specific or credible threats to the games.
(Copyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.)
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