A controlled explosion has been carried out on a suspect device found outside Hammersmith Tube station in west London, police have said.
Hammersmith Station was closed during the alert
The station and surrounding roads were closed while emergency services dealt with the scare at about 0825 BST.
The alert comes amid a raised security threat following the failed terrorist attacks in London and Glasgow.
There was an unconfirmed report that the suspect objects had turned out to be three abandoned fire extinguishers.
"These are the kinds of challenges we face in London every day," said Ch Supt Ali Dizai. "We can't afford to take any chances."
Up to 8,000 commuters were forced to find alternative routes into work as Hammersmith and Barons Court stations were closed for an hour.
There were severe delays for motorists as Hammersmith Broadway was closed between King Street and Shepherd's Bush Road as well as Hammersmith Bridge.
Tower Hill and East Ham Tube stations, which were shut in a separate alert, have also reopened.