Britain Arrests 3 Men at 2 Airports

LONDON — British authorities Thursday arrested a man at Gatwick Airport who allegedly had a grenade in his luggage and detained two men outside Heathrow Airport, during a high alert against terrorism.

The two airports are the focus of a huge security operation in London, set in motion this week in response to a threat that Prime Minister Tony Blair has refused to detail. He again kept quiet when Parliament pressed him Thursday.

Gatwick’s North Terminal was closed for hours, and flights at the terminal were suspended after police reportedly found the grenade in the baggage of a 37-year-old Venezuelan upon his arrival on a British Airways flight from Caracas, Venezuela.

At Heathrow, police said two men were arrested in nearby Hounslow as a precaution and were not believed to be linked to the security alert. They would not detail why the men were being held.

Britain has deployed hundreds of soldiers at Heathrow, Europe’s busiest airport, in the last three days after police warned that the Al Qaeda terrorist network might try to attack London this week.

Police refused to comment on a Guardian newspaper report that the alert was sparked by intelligence that Islamic extremists had smuggled SAM-7 antiaircraft missiles into Britain.