The Metropolitan Police are investigating a suspicious package that had been delivered to an office within the Palace of Westminster. The letter contained white powder, officers say.
"At approximately 1136hrs on Tuesday, 13 February, police were informed of a suspicious package that had been delivered to an office within the Palace of Westminster," police said in a statement.
"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 "heavy" presence of officers was reported on a ministerial corridor, which is below the House of Commons chamber, and where some government ministers have their offices.
“The police are currently investigating an incident on the parliamentary estate," a House of Commons spokesperson said, according to Reuters.
Britain's parliament is currently in recess, which means most ministers are not in Westminster.
The Palace of Westminster was not locked down and the main Carriage Gate entrance - the scene of the attack on Westminster last March - was open as normal.
Roads surrounding parliament were not closed off.
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