Donald Trump's son targeted with substance found in mail to his home

NEW YORK, March 18 (UPI) -- Eric Trump, son of Republican presidential front-runner Donald Trump, received a package containing a suspicious white powder to his home, though investigators determined it was harmless.

The 32-year-old was mailed the package Thursday evening at his New York City apartment inside a building his father owns on upscale Central Park South. A spokesman for the New York Police Department confirmed investigators were sent to Trump's home. The spokesman said the white powder was field tested and it turned up negative for hazardous substances.

ABC News reported the letter carried a Boston postmark and contained a note: "If your father does not drop out of the race, the next envelope won't be a fake." It was signed "X."

The mysterious note comes after the hacker group Anonymous declared "total war" against Trump. The group said it had published Trump's cellphone number and home address and other pieces of personal information, though UPI was not able to verify whether the number was, in fact, Trump's.

It was also not clear whether Eric Trump's personal information was included in the Anonymous data dump.