Terrorists warn of Heathrow attack on Twitter

Terrorists that claim to support the Islamic State have used Twitter to threaten an attack on London's Heathrow airport, a media report said today.

An alert from the SITE Intelligence Group yesterday warned that a "pro-Islamic State" account had issued threats against aircraft "flying from Heathrow to the US" this weekend, which coincides with the American Independence Day holiday, The Times reported.

The alert warned of a potentially deadly device being placed at Heathrow, Los Angeles airport or JFK in New York.

Lord Ahmad of Wimbledon, UK transport minister, urged the public to be "vigilant".

"We all need to be vigilant to the threat of terrorism. In the UK we keep all aspects of aviation security under constant review and work closely with our international partners to mitigate risks. We will continue to take all steps necessary to keep the public safe but for security reasons we do not comment in detail on specific measures or operational matters," he said. Heathrow has also declined to comment.