Meghan Markle and Prince Harry had a recent security scare, when a white substance was sent in an envelope addressed to the couple along with a threatening letter, a source tells ET.
Metropolitan Police confirmed on Thursday that police are investigating after a package containing a substance was delivered to St James's Palace in London, England, on Feb. 12. The substance was tested and confirmed as non-suspicious, and officers are also investigating an allegation of malicious communications that relates to the same package, which is being treated as a racist hate crime.
No arrests have been made, and the matter is being investigated by officers from the Met's Counter Terrorism Command.
According to our source, the letter was addressed to Kensington Palace where Harry lives, however, it went through a sorting system at St. James's Palace and was intercepted there.
“The substance was tested and determined not to be anthrax," the source says. "The letter never actually made it to Kensington Palace due to security systems in place."
The source also says there were "racist undertones in the letter." Meghan has spoke out about her struggles growing up bi-racial in the past -- her father, Tom, is Caucasian, while her mother, Doria, is African American.
Not surprisingly, the source adds that security at Windsor Castle, where Meghan and Harry are set to marry on May 19, will be extremely tight.
“Planning for their wedding is ongoing, including a huge security presence in Windsor,” the source notes.
Meanwhile, it looks like 36-year-old Meghan and 33-year-old Harry aren't letting the scare affect their daily lives. The pair enjoyed a date night last Friday, watching Hamilton at the Victoria Palace Theatre in London's West End.
For more on Meghan and Harry's upcoming royal wedding, watch the video below: