England fans on the way to the World Cup are being screened at Heathrow Airport in a bid to catch those trying to defy football banning orders.
Banning orders are designed to stop trouble-makers travelling
The screening is part of Operation Jardon, begun on Sunday to try to stop banned fans travelling to Germany.
British Transport Police are also at Waterloo International and Ashford International railway stations.
The banning orders prevent travel to the World Cup and require attendance at a police station for England matches.
Operation Jardon is a national initiative targeting airports, ports and railway stations.
In London, the Metropolitan Police have been visiting pubs and clubs to advise managers about responsible drinking, particularly on match days.
There will also be extra police presence in the capital to deal with increased crowds when England are playing.
The Met Police's Commander Bob Broadhurst says the policing operation during the tournament will be "low key".
"Our priority is to make sure that this is an enjoyable tournament for everyone, wherever they watch it," he said.
"However, people should be aware that if they do cause trouble then they will be immediately liable for a football banning order."
The 3,286 people nationwide who are subject to the banning orders received letters last month ordering them to hand in their passports to police.
Those who fail to do so could face six months in prison and a £5,000 fine.
England kick off their World Cup campaign against Paraguay in Frankfurt on Saturday, and will also play Trinidad & Tobago and Sweden in Group B.
Striker Wayne Rooney will have a scan on his broken metatarsal on Wednesday to determine whether he is fit enough to rejoin the England squad.
The tournament opens with the host nation facing Costa Rica in Munich on Friday.