A man and woman were taken to hospital as a precaution after a suspicious package was reported at a Parliamentary building.
The package was contained to one room of the Norman Shaw building, off the Victoria Embankment in Westminster .
It was reported to police at 12.58pm on Monday (March 12) and investigated.
The package was reportedly sent to the office of Labour MP for Bedford, Mohammed Yasin.
Metropolitan Police has now declared the substance as non-hazardous.
A spokesman for Metropolitan Police confirmed that two people, a man and a woman, had been taken to hospital as a precaution following the alert.
Exactly a month before Monday's incident, on February 12, a suspicious white powder was sent to Prince Harry and Meghan Markle at St James' Palace.
The powder was tested and later declared as non-suspicious.
The following day, on February 13, a letter containing a white powder was also sent to Home Secretary Amber Rudd at her parliamentary address.
Ms Rudd happened to be in America at the time of the incident, which forced a shut down of some offices while police investigated.
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