Armed police have evacuated people from the area near St. Thomas Hospital in London while Westminster Bridge has been closed amid an ongoing security operation.
There was no immediate confirmation of the nature of the incident from either the police or the hospital administration.
Local media are reporting that doctors, nurses and patients at the hospital have been placed on a security lockdown, with people being prevented from entering the building by armed police.
The hospital is located near Waterloo Station and the Houses of Parliament.
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