President Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE on Thursday suggested mental illness played a role in a shooting at a Florida high school that left 17 dead.

“So many signs that the Florida shooter was mentally disturbed, even expelled from school for bad and erratic behavior," Trump tweeted.

"Neighbors and classmates knew he was a big problem. Must always report such instances to authorities, again and again!”

So many signs that the Florida shooter was mentally disturbed, even expelled from school for bad and erratic behavior. Neighbors and classmates knew he was a big problem. Must always report such instances to authorities, again and again! — Donald J. Trump (@realDonaldTrump) February 15, 2018

ADVERTISEMENT

Authorities said Nikolas Cruz, 19, opened fire Wednesday at Marjory Stoneman Douglas High School in Parkland, Fla., killing 17 and wounding many others. Cruz was taken into custody shortly after the shooting.

The Miami Herald reported that the suspect previously attended the school, and had been flagged as a potential threat. Cruz was reportedly kicked out of school after he brought ammunition with him in his backpack, and spoke frequently about guns and knives.

Cruz had no previous arrests, the Herald reported.

Trump on Wednesday offered his prayers and condolences to the victims' families, saying "no child, teacher or anyone else should ever feel unsafe in an American school."

My prayers and condolences to the families of the victims of the terrible Florida shooting. No child, teacher or anyone else should ever feel unsafe in an American school. — Donald J. Trump (@realDonaldTrump) February 14, 2018

As reports of the death toll came in, a number of Democrats called on Congress to act to curb gun violence, while Republicans shared their thoughts and prayers with the victims and their families.

Sen. Marco Rubio Marco Antonio RubioFlorida senators pushing to keep Daylight Savings Time during pandemic Hillicon Valley: DOJ indicts Chinese, Malaysian hackers accused of targeting over 100 organizations | GOP senators raise concerns over Oracle-TikTok deal | QAnon awareness jumps in new poll Intelligence chief says Congress will get some in-person election security briefings MORE (R-Fla.) warned against making assumptions about a cause for the shooting.

"I think it's important to know all of that before you jump to conclusions that there was some law that we could have passed that would have prevented it. And there may be, but shouldn't we at least know the facts?" Rubio said on Fox News.