NEW YORK (FOX5NY) - The wife of Donald Trump Jr. was taken to the hospital as a precaution after opening an envelope containing a white powder, which turned out to be harmless.
The letter was sent to a Manhattan apartment owned by Vanessa Trump, the president' daughter-in-law. Her mother lives in the home.
Vanessa Trump reportedly opened a letter about 10 a.m. that was addressed to her husband. Police said that she called 911 a short time later and said she was coughing and felt nauseous.
Fox News reported that she was taken to the hospital as a precaution and there was no indication anyone suffered injuries. A preliminary test of the powder indicated it wasn't dangerous, a police spokesman said.
Sources told Fox 5's Linda Schmidt that the substance was cornstarch and that the envelope had a Boston postmark.
Detectives from the NYPD's Intelligence Division and Secret Service agents are investigating.
"The Secret Service and our law enforcement partners in New York City are investigating a suspicious package addressed to one of our protectees received today in New York, New York," the Secret Service said in a statement to Fox News. "This is an active investigation and we cannot comment any further."
President Trump spoke to Vanessa Trump, White House spokeswoman Sarah Huckabee Sanders said. Sanders said she could not comment further because of the investigation.
Trump Jr. tweeted: '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 behavior.
Fox News reported that Trump Jr. ditched his Secret Service detail for a period of time in September, reportedly because he wanted more privacy. But his detail was apparently reactivated about a week later.
The Trump Organization didn't immediately respond to a request for comment.
Correction: This story has been updated to reflect that one person was hospitalized.
The Associated Press contributed to this report.