LONDON — British police say they have released without charge one of seven people arrested over an alleged plot to launch a terrorist attack. The Metropolitan Police said Sunday that a 30-year-old woman detained in London Thursday has been freed. Five men and a woman are still being question over allegations of “the commission, preparation or instigation of acts of terrorism.” The suspects include a British Muslim convert and three brothers who were detained Thursday by armed police at their home near London's Olympic Park. Counter-terror officers are on high alert ahead of the Games, which begin July 27, but police say the arrests are not connected to the Olympics. Britain's terrorist threat risk remains at substantial, the middle point on a five-point scale, meaning an attack is a strong possibility. Meanwhile, a terror suspect in Britain charged with breaking restrictions on his movements had crossed through London's Olympic Park five times, newspapers reported Sunday. The 24-year-old – named only as CF – is suspected of being a militant for Somalia's Al-Qaeda-allied Shabab fighters, The Sunday Telegraph and the Sunday Mirror said. He is one of nine people suspected of being a risk to national security. — Agencies