A suspicious package addressed to Joe Biden, former vice-president of the US, was found at a postal facility in Delaware on Thursday morning.
The package found at the Hares Corner postal facility, and reported to police around 5:50am, is similar to others sent to prominent national Democrats in recent days.
Investigators from the FBI, US Postal Inspection Service, Delaware State Police and New Castle County police stormed the United States Postal Service facility along Quigley Boulevard in New Castle, Delaware after the explosive was intercepted.
The bomb squad deployed a robot as they investigated.
Wilmington Police also closed Chestnut Street from DuPont to Broom streets behind the Lancaster Avenue post office in Wilmington as they investigated the suspicious package.
The new developments in Delaware came as a device was removed from a lower Manhattan property belonging to actor and Trump critic Robert De Niro.
Others were mailed to offices and homes of prominent Democrats and public figures, including one sent to CNN offices in New York City.
Packages addressed to Hillary Clinton, former President Barack Obama, billionaire George Soros, ex-Attorney General Eric Holder, former CIA director John Brennan and Maxine Waters of California — who was sent two — all appear to have the same characteristics.
None of the devices detonated and no one was injured, and authorities are examining the crude explosives and staying on the lookout for additional packages.
The search for whoever built the possible explosive devices continues.
The Delaware response came the morning after a suspicious package was found near the Montgomery County, Pennsylvania, office of Tom Murt, Republican state representative.
A bomb disposal unit was called in and the package was determined to not be explosive.
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