Police are currently investigating a package of white powder found at Parliament in Westminster, a House of Commons spokesperson said.
The Met Police said at approximately 11:36am, officers were informed of a suspicious package that had been delivered to an office within the Palace of Westminster.
"Police are at the scene and dealing," the Met said.
The letter contained a white powder which is currently being assessed by specialists. The office remains closed at this time, but the rest of the Palace of Westminster is open.
Detectives from the Met’s Counter Terrorism Command have been informed and are investigating.
A police officer told Press Association earlier this afternoon that a suspicious package had been found, and said: "We haven’t been told much but a package has been left... It won’t be anything to worry about."
Witnesses reported seeing a heavy police presence around the Houses of Parliament.
Parliament is currently in recess, with MPs on a break until 20 February.
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