Two men have been arrested near Heathrow Airport as a "precautionary measure" under anti-terrorist legislation, police have said.
The men were arrested in Hounslow and have been taken to Paddington Green police station in central London for questioning, a Scotland Yard spokesman said.

In a separate development, Gatwick Airport's North Terminal has been closed and evacuated because of a security alert.

Sussex Police would not give any further details or say whether it had anything to do with the present state of alert in the UK.

The terrorist must not be able to assess what we know or how we know it



David Blunkett

A Gatwick spokesman said departing flights from the North Terminal were suspended until further notice but South Terminal flights were currently unaffected.

The airport is on heightened alert along with other UK airports this week, with extra armed police drafted in to patrol the perimeter and terminal buildings, and check cars in the surrounding area.

Two men were earlier stopped in their car near Heathrow Airport's perimeter fence, by police carrying out routine checks as part of the increased security operation.

No weapons were found but officers were not satisfied with the answers the two men gave and arrested them as a "precautionary measure", the spokesman added.