THE wife of Donald Trump Jr was taken to hospital after the President's eldest son was sent a package containing a white powder.
Vanessa Trump opened the letter at around 10am at the couple's apartment in the Sutton Place neighbourhood of New York.
NBC said a preliminary investigation suggested the substance sent to the couple's home was not hazardous and that Ms Trump, her mother and one other person were taken to hospital as a precautionary measure.
The package was reportedly addressed to the 40-year-old Mr Trump Jr, who with his brother Eric, has been running the Trump Organisation since their father was elected to the White House.
The Associated Press said, Ms Trump Jr dialled 911 and that she was taken to hospital after coughing and saying she felt nauseous.
"The substance had arrived by mail and it was addressed to Donald Trump Jr," said New York Police Department spokesman Carlos Nieves.
The Trump Organisation did not immediately respond to a request for comment. It is unclear what the powder was.
Mr Trump Jr later said on Twitter: "Thankful that Vanessa and my children are safe and unharmed after the incredibly scary situation that occurred this morning. Truly disgusting that certain individuals choose to express their opposing views with such disturbing behaviour."
ABC said it was not known if any of the couple's five children were at home at the time of the incident. It said the New York Police Department and the Secret Service were investigating the incident.
Mr Trump Jr, who married his wife at his father's Mar-a-Lago estate in Florida in 2005, apparently dropped his Secret Service detail for a period of time last.
He did so because he wanted more privacy, yet the team was reassigned about a week later.
US authorities have been on alert for mail containing white powder since 2001, when envelopes laced with anthrax were sent to media outlets and US lawmakers, killing five people.
President Trump spoke with his daughter-in-law on Monday afternoon, White House spokeswoman Sarah Sanders said, declining further comment on the investigation
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