In a pre-dawn swoop, the Scotland Yard on Monday raided a mosque in north London and arrested seven people in connection with investigations into the recent discovery of traces of a deadly poison
The poison, ricin [a poisonous protein in the castor bean], had been discovered in nearby Wood Green earlier in the month.
The mosque in Finsbury Park has attracted controversy over its connection with radical Muslim cleric Sheikh Abu Hamza.
The Charity Commission wants Hamza expelled as an agent of the North London Central Mosque trust, which runs the mosque, because of his "political" preaching.
At least 150 police personnel carrying arms, ladders and battering arms raided the mosque at 0730IST.
Two helicopters were seen circling overhead, training spotlights on the north London mosque and two neighbouring three-storeyhouses, which were also raided.
AScotland Yard spokesman said the raid was part of extensive investigations into terror activities in the United Kingdom.
"Althoughthis is linked to arrests made in north London, at this stage there is nothing to suggest chemical substances are on the premises. Seven people have been taken for questioning," he told reporters.
The seven suspects, who were living in the mosque, were arrested under the Terrorism Act 2000and taken to central London police station.