WASHINGTON – Three days after addressing the National Rifle Association convention, President Donald Trump told the NRA on Monday to straighten out in the wake of a leadership crisis and a high-profile investigation into its finances.

"It must get its act together quickly, stop the internal fighting, & get back to GREATNESS - FAST!" Trump said in a morning tweet.

Turmoil marked the NRA convention in Indianapolis as President Oliver North announced he would not seek a second term and expressed concern about how the organization spends its money.

Longtime NRA executive Wayne LaPierre accused North of trying to force him out of the organization. Hours after Trump's tweet on Monday, the NRA Board of Directors re-elected LaPierre as the organization's executive vice president and CEO.

The New York Attorney General's Office announced Friday that it would open an investigation into the group's tax-exempt status.

During his NRA speech, Trump praised LaPierre and North as "extraordinary champions for the Second Amendment" and gun rights in general. He singled out North as a "great guy" but did not mention the infighting between him and LaPierre.

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Trump underscored his support for gun rights, an issue popular with many of his supporters.

The president waited until Monday to address the group's problems. He also criticized New York Gov. Andrew Cuomo and the state attorney general's office.

"The NRA is under siege by Cuomo and the New York State A.G., who are illegally using the State’s legal apparatus to take down and destroy this very important organization, & others," Trump said.

New York State Attorney General Letitia James said during her campaign last year that she would investigate the NRA's status as a not-for-profit civic organization that is exempt from taxes. "The NRA has an office here in New York state," she said, "and what we want to do is investigate to see whether or not they have in fact complied with the not-for-profit law in the state of New York."

In a written statement after Trump's tweets Monday, James' office said the attorney general is "focused on enforcing the rule of law. In any case we pursue, we will follow the facts wherever they may lead."

It added, "We wish the President would share our respect for the law.”