U.S. Republican presidential hopeful Marco Rubio said his staff was safe after his Washington campaign headquarters was evacuated over a suspicious white powder.
"Glad campaign staff in DC is all safe! Thanks to DC emergency personnel," Rubio said in a tweet.
Campaign spokesman Alex Conant told the Washington Post that the substance, which was found by a worker in an envelope at around 4 p.m., turned out to be laundry detergent.
Rubio was campaigning on Tuesday in his home state of Florida, one of five states holding primaries for the Republican party.
A suspicious substance found at the Houston campaign headquarters of U.S. Republican presidential contender Sen. Ted Cruz last week was determined to be nontoxic, a local media report said, citing a Cruz campaign official.