New York's attorney general is suing Donald Trump, his children and the Trump Foundation, alleging what she called "extensive and persistent violations of state and federal law".
The lawsuit also states that Trump used the foundation to cover legal fees, promote his properties and businesses. I won't settle this case!,' he wrote.
NY is also seeking $2.8 million of restitution plus penalties, a 10-year ban on Trump serving as a director of a NY nonprofit, and one-year bans for his children Donald Jr, Eric and Ivanka.
Donald Trump hit back at the lawsuit on Twitter, saying that "sleazy NY democrats" were "doing everything they can to sue me on a foundation that took in $18,800,000 and gave out to charity more money than it took in, $19,200,000".
Underwood is also seeking restitution of the $2.8 million she says was paid to the presidential campaign and penalties.
Underwood was promoted to attorney general a fews weeks ago, succeeding Schneiderman after he resigned following allegations that he had physically abused several romantic partners.
US President Donald Trump is joined by US First Lady Melania Trump (2nd R front), his daughter Ivanka Trump (2nd L front) and her husband Jared Kushner (L front) during the presidential inaugural parade on January 20, 2017 in Washington, DC.
President Donald Trump's charitable foundation has persistently broken state and federal laws with improper political activity, self-dealing and failing to follow basic fiduciary obligations, NY said in a lawsuit seeking to dissolve the organization. But those presidential powers couldn't be applied to state level prosecutions such as the one in NY.
In a statement, Ms Underwood said Mr Trump had illegally instructed his foundation to provide support to his presidential campaign by using the foundation's name and funds it raised to promote the campaign. Underwood said she has sent letters to the Internal Revenue Service and Federal Election Commission for further investigation.
The Trump Foundation has been in legal limbo since after the election, when the president wanted to dissolve it amid growing controversy about its practices. Schneiderman ordered the foundation to stop fundraising in NY.