LONDON - On the third day of one of Britain's biggest security alerts, authorities closed part of a major London airport and suspended flights yesterday after a 37-year-old Venezuelan arrived from South America with a hand grenade in his luggage.
The explosive was found when the man's bags were searched after his British Airways flight from Colombia landed at Gatwick Airport, south of London, police said. After the discovery, flights from Gatwick's North Terminal were suspended.
Also yesterday, two men were arrested near Heathrow Airport, police said. Authorities were on alert after the British government issued a warning Tuesday that al-Qaida operatives might be planning to fire an anti-aircraft missile at a commercial airliner. The two men were found along a flight path leading to Heathrow, which is west of London, but they had no weapons.
The police said that neither the Venezuelan man arrested at Gatwick nor the two men taken into custody near Heathrow were believed to be linked to an al-Qaida threat.
For the past three days, armed police officers have patrolled Heathrow Airport, supported by troops deployed at the airport for the first time since 1994. The head of the Metropolitan Police in London, John Stevens, said authorities had considered closing Heathrow.
With officials insisting that Britons face what Home Secretary David Blunkett called a "real and serious threat" of a major terror attack, police also announced that they would limit access today to a third airport at Stansted, north of the capital.
Other security measures taken yesterday included a Royal Air Force Nimrod surveillance plane prowling the skies over the British capital.
Britain issued the terror alert this week because of fears that an al-Qaida attack would be launched to coincide with the major Muslim festival of Eid al-Adha, which marks the end of the annual hajj pilgrimage to Mecca.
British officials reportedly were frustrated last night that the security alert had not netted any terrorists linked to al-Qaida.
The newest security alert and the prospect of British soldiers being sent to war in Iraq have unnerved many in this nation. Both of Britain's main opposition parties urged the government to persuade Britons "that this is not a stunt and should be taken seriously."
But the authorities have not given a full explanation of the alert beyond saying that the threat is real.
Prime Minister Tony Blair told reporters yesterday that "the threat that preoccupies not just this country but other countries throughout the world is the threat of disorder and chaos."