Police say they are dealing with a security incident at St Thomas’ hospital in central London, with nearby Westminster Bridge leading to parliament closed to traffic.
Police said they would provide more information when they know more. There was no immediate comment from the hospital.
The alert was being stood down, police said and road closures in the area were being lifted.
Lambeth police said on Twitter there were no arrests.
Officers tweeted: “Police were called at 9.18 to St Thomas’ hospital SE1 following a report of threats made by a male. No weapons were seen. Armed officers attended. Local road closures were put in place. The hospital was not evacuated.
“Officers subsequently located and spoke to a male inside the hospital. The incident was stood down at approximately 10.30. There have been no arrests. This was not treated as a terrorism incident.”