A counter-terrorism investigation is being carried out after a "suspicious package" containing white powder was delivered to an office at the Palace of Westminster on Tuesday (February 13).
The letter was delivered at around 11.36am to the office, which was closed by police to allow specialist officers to assess the contents.
A Met spokesman said: “Police were informed of a suspicious package that had been delivered to an office within the Palace of Westminster.
“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.”
Specialist officers investigating the suspicious package later found it contained a “non-harmful” powder, a spokesman for the House of Commons said.
A message was put out on the annunciators which are displayed on TV screens around Parliament reading: “Incident in the House of Commons is being dealt with by Metropolitan Police.”
“Do not be alarmed,” the messaged added.
Detectives from Scotland Yard have confirmed its Counter Terrorism Command is now investigating.
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