LONDON -- Osama bin Laden's al-Qaida network has a "substantial presence" in Britain, the head of London's Metropolitan Police said Sunday.
John Stevens said it was difficult to know how many al-Qaida cells were active in Britain. "But we do know there is a substantial presence, and we are taking action," he told the British Broadcasting Corp.
In the past week, Britain has been on a heightened state of alert, with increased security at several airports across the country. More than 400 troops were stationed at London's Heathrow airport last week and police have bolstered the number of officers at several sites around London.
Police said Sunday that a 37-year-old Venezuelan arrested Thursday after a suspected live hand grenade was found in his luggage at Gatwick airport had been charged under the Terrorism Act.
Hasil Mohammed Rahaham-Alan was charged with possession of explosives, possession of items for terrorist purposes and carrying a dangerous item on a flight. He was arrested after arriving on a flight from Caracas. The discovery led officers to shut the airport's North Terminal for several hours.
Rahaham-Alan was due to appear today at London's Bow Street Magistrates Court.
A diplomatic source said the suspect apparently was carrying a U.S.-made grenade inside a duffel bag. The suspect wanted to take the bag on the plane as hand luggage but was forced to check it before flying because it was too big.