The wife of Donald Trump Jr has been taken to a New York hospital along with two other people after opening mail containing white powder.
Vanessa Trump, the wife of Donald Trump Jr, and two other people were taken to a New York hospital on Monday after she opened a piece of mail containing an unidentified white powder that was later determined to be non-hazardous, officials said.
"The substance had arrived by mail and it was addressed to Donald Trump Jr," New York Police Department spokesman Carlos Nieves said.
Vanessa Trump, the daughter-in-law of US president Donald Trump, was hospitalised after she complained of nausea following her exposure, New York officials said.
Three patients from the household were transported to the New York-Presbyterian/Weill Cornell Medical Centre for further evaluation, Fire Department spokeswoman Sophia Kim said.
The three included Vanessa Trump's mother, although she had not complained of symptoms, the police spokesman said.
The package had a Boston postmark, ABC News and the New York Post reported, citing unnamed law enforcement sources. NYPD officials declined to comment on that detail.
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.
The US Secret Service, which is charged with protecting members of the president’s family, has joined the investigation, spokesman Jeffrey Adams said. White House officials had no immediate comment.
The apartment building where the incident occurred is in Manhattan's Sutton Place neighborhood close to the East River. The apartment may be the home of Vanessa Trump's mother, local news outlets reported.
Donald Trump Jr, the president's eldest son, has been in the public eye for his role in 2016 meetings with a Russian attorney and others where the Trump campaign was offered potentially damaging information about Democratic rival Hillary Clinton.
Congress has held probes into those meetings and whether they were part of a Russian campaign to influence the 2016 US presidential election.
Russia denies trying to influence the election. Mr Trump dismisses any talk of collusion.
In 2016, white powder, which also proved harmless, was sent to the home of Eric Trump, Mr Trump Jr’s brother.