London Bridge railway station reopened on Wednesday afternoon hours after a suspicious package was found onboard a train.
Armed police were called to the scene, south of the River Thames, shortly after 12.30pm London time.
The station was evacuated as a precaution while specialist officers assessed the item.
British Transport Police said the suspect package was not a threat.
“Specialist officers have now assessed the item as non suspicious, and the station will be reopening. We always take these reports seriously,” a statement said.
Daniel Coonan tweeted that police had forced passengers out of the area.
“Strange scenes in London. The police are everywhere evacuating the station and forcing people off the platforms,” he said.
“Londoners typically demanding the police to tell them why they can’t get a train to where they want to get to. Multiple helicopters in the sky above.”
Another passenger told of the moment she was told to leave her train.
“Calmly minding my business when police board my train and say there’s a suspicious package in the carriage next to mine and that I have to evacuate the train,” she tweeted.
“Then we had to evacuate the platform. Then we had to evacuate the station.”
National Rail said passengers should expect severe delays after trains were earlier diverted away from the area.
“Lines have reopened at London Bridge following the emergency services dealing with an incident at this station,” the company said.
Social media images from the scene showed officers standing guard outside the station entrance while the item was examined.