Donald Trump Jr said he was disgusted and disturbed after his wife Vanessa Trump was hospitalized Monday morning when she opened a letter with a white powder inside.

The former model, 40, was at her parents' apartment in a building in Manhattan's Midtown East around 10am when she opened the letter addressed to her husband and started coughing and feeling nauseous, a source with direct knowledge of the incident told DailyMail.com

Trump's mother Bonnie Haydon handled the letter before passing it on to her daughter, according to the New York Post.

The mother and daughter and another person were decontaminated and taken to New York Presbyterian-Weill Cornell Medical Center as a precaution, New York City Fire Department officials said. They appear to be fine now.

Law enforcement sources told the Post that the powder turned out to be cornstarch.

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Vanessa Trump was hospitalized on Monday after opening a letter with a white powder inside of it. She's pictured above with her husband, Donald Trump Jr., in April 2016

Donald Jr tweeted that he was glad that his wife and children 'are safe and unharmed'

A Hazmat truck is seen outside Vanessa Trump's parent's apartment building on Monday

The view outside NewYork-Presbyterian/Weill Cornell Medical Center where Mrs Trump was taken on Monday

Officially though, an NYPD spokesman wouldn't say what the powder was but said it was 'deemed to be non-hazardous' and is being taken to their lab for 'further analysis'.

The NYPD's intelligence division and the Secret Service are investigating the incident.

'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. This is an active investigation and we cannot comment any further,' the Secret Service said in a statement.

The daughter-in-law of President Trump and former model is pictured above in new York City on January 31

Sister-in-law Ivanka Trump sent her thoughts from Washington, DC after the incident on Monday

'Thankful that Vanessa & 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,' Donald Jr tweeted after the incident.

President Donald Trump spoke to his daughter-in-law on Monday after she arrived at the hospital.

White House press secretary Sarah Sanders told reporters at around 4:00 p.m. that the two had talked on the phone 'in the last hour.'

Donald Jr's sister Ivanka sent her thoughts from Washington, DC.

'Thinking of @MrsVanessaTrump & wishing I was by her side today. No one deserves to be frightened this way. There is no excuse,' she tweeted

President Trump's personal lawyer, Michael Cohen, weighed in with a statement of his own.

'How disturbed must a person be to do what they did to a mother of five young children? This dangerous and reckless act goes beyond political differences,' Cohen said according to the Post.

The incident recalled the scary days after 9/11 when letters containing lethal anthrax spores were sent to the offices of several politicians and media outlets - resulting in five deaths.

Donald Jr, 40, is the eldest son of President Trump, followed by his sister Ivanka, 36; brother Eric, 34; half-sister Tiffany, 24; and half-brother Barron, 11.

As a child of the president, Donald Jr and his family were assigned a Secret Service detail when his father was elected. He voluntarily gave up his Secret Service protection in September, wanting more privacy, but his detail was reinstated about a week later.

Donald Jr and his wife are pictured above with four of their five children voting on election day in 2016

Don Jr and model Vanessa Hayden married in August 2005 at his father’s Mar-a-lago estate in Palm Beach, Florida. The pair were actually introduced by the future president when Don Jr attended a fashion show with his father the previous year. Having met at the beginning of the show, Trump Sr was said to be so smitten with Vanessa that he re-introduced his son to her at intermission. ‘Donald comes back up to me again, “I don’t think you’ve met my son Donald Trump Jr,’ Vanessa told The New York Times in 2006. She responded "Yeah, we just met, five minutes ago".

The couple finally started a relationship after being introduced a third time at a party by a mutual friend. Trump Jr, then 26, proposed to her in front of a jewelry store, complete with paparazzi, with a $100,000 engagement ring, which he is said to have wrangled for free in return for publicity.

They have five children, daughters Kai, 10, and Chloe, three; and sons Donald III, eight, Tristan, six, and Spencer, five – all of whom regularly feature on Don Jr’s Instagram account.

Since his father and sister Ivanka moved to Washington, DC., Donald Jr and his younger brother Eric have taken over control of their family company.

Last year, Eric was sent a threatening letter with a white powder in it to his New York City apartment as well.