LONDON: Police on Tuesday evacuated Terminal Four at London's Heathrow Airport while experts checked a "suspicious item", witnesses and police and airline spokesmen said.
People were cleared from the building because "we have a suspicious item which we are checking out", a spokesman at London's Metropolitan Police said.
A spokesman for British Airways said delays could be expected to departures, but gave no further details of the incident, which comes amid heightened alert following failed bombings in London and Glasgow.
An airline passenger told AFP that all passengers and staff -- which estimated numbered around 2,000 in all --were evacuated outside the building and that three fire engines and an ambulance arrived with their lights flashing.
However, he said the "mood is quite calm", and that KLM and BA staff were asked to return to the building while passengers still awaited instructions.
The passenger said the evacuation was prompted by the discovery of what the authorities described as a "suspicious bag".
Britain raised its national security threat level to "critical" at the weekend after two failed car bombings in London on Friday and an attack at Glasgow airport on Saturday.
