Prince Harry and his fiancée Meghan Markle have been sent white powder claimed to be anthrax in a malicious hoax.
The package was intercepted by officials at and found to be harmless by police, who have launched an investigation.
Officers from the Metropolitan Police’s counter-terrorism command were called to the alert earlier this month, according to London’s Evening Standard newspaper, which originally reported the story.
“Police are investigating after a package containing a substance was delivered to St James’s Palace on 12 February.
“The substance was tested and confirmed as non-suspicious. Officers are also investigating an allegation of malicious communications which relates to the same package.”
There have been no arrests and enquiries continue.
It came the day before white powder was sent to Amber Rudd’s office in the Houses of Parliament alongside a rambling letter on the issue of radicalisation.
Police are investigating if there is a link between the two incidents, which came after a series of hoaxes involving white powder across the UK.
Targets have included mosques and Islamic centres, sparking an investigation into a potential far-right hate campaign last year.
The latest scare came three months before Prince Harry and Ms Markle, an American actress known for her humanitarian work, are to marry.
The couple live at Nottingham Cottage, in the grounds of Kensington Palace, where the Duke and Duchess of Cambridge and their children reside when they are in London.
St James’s Palace, in the heart of Westminster, is home to other members of the royal family including princesses Beatrice and Eugenie, and is used as a ceremonial meeting place.
A Palace spokesperson declined to comment on the incident.
