Police have evacuated the House of Commons office of Liberal Democrat leader Jo Swinson after she was sent a parcel containing a suspicious powder.
Specialist officers attended the scene and cordoned off the immediate area, although the building was not evacuated.
Police were called after a staff member opened the package on Monday morning. Ms Swinson is not believed to have been present at the time.
It was later confirmed that the package was not dangerous.
Ms Swinson’s office is on the third floor of Portcullis House, a large office building that forms part of the parliamentary estate.
In a statement, the Metropolitan Police said: “Police attended Portcullis House, Westminster at 0951hrs today following reports of a suspicious package delivered.
“Officers attended and the contents of the package are being assessed. No reports of any illnesses or injuries. The premises have not been evacuated. Enquiries continue.”
A later statement added: “The package delivered to Portcullis House, Westminster at 0951hrs today has now been assessed as non-suspicious.”
The incident comes amid warnings of threats to MPs campaigning in the run-up to 12 December general election.
Some MPs seeking re-election have revealed that they are carrying panic alarms on police advice. These are directly linked to police networks and could trigger an armed response if used.
Rosie Duffield, the Labour MP for Canterbury, told ITV News that officers have also told MPs not to campaign alone after dark.
A number of MPs, including Conservatives Nicky Morgan and Caroline Spelman, former Labour MP Louise Ellman and Lib Dem Heidi Allen have also cited abuse as among their reasons for standing down at the election.
