Rep. Maxine Waters, whose call for public protests of Trump administration officials has triggered a debate over civility in politics, said Thursday that she has canceled events in Texas and Alabama this weekend after a “very serious death threat” against her.

In a statement reported by CNN, the California Democrat said that after President Trump took aim at her Monday on Twitter, “even more individuals are leaving threatening messages and sending hostile mail to my office.”

“There was one very serious death threat made against me on Monday from an individual in Texas which is why my planned speaking engagements in Texas and Alabama were canceled this weekend,” Waters said in the statement.

A Waters spokeswoman did not immediately respond to a request for confirmation.

Waters had been scheduled to speak Friday morning at the annual legislative conference of the National Organization of Black Elected Legislative Women in Birmingham, Ala.

In a statement Friday, the group said that Waters would not be participating in the conference “due to unforeseen circumstances.”

“We regret that Representative Waters will not join us this year,” Karen Camper, national president of NOBEL Women, said. “Maxine Waters’ strength, determination and spirit always inspires us and will permeate throughout this conference.”

The details of Waters’s Texas event were not immediately known.

Waters has been rebuked by Republicans and Democrats after calling at a Los Angeles rally last weekend for demonstrators to harass Trump’s Cabinet officials wherever they go amid an escalating debate over immigration policy.

Taking to Twitter, Trump fired back by calling Waters “an extraordinarily low IQ person” and warning her to “be careful what you wish for.”

According to CNN, Waters said in the statement that Capitol Police are investigating several other threats in which people have vowed “to shoot, lynch, or cause me serious bodily harm.”

Eva Malecki, a Capitol Police spokeswoman, said the department does not comment on ongoing investigations.

The news came on the same day that a gunman opened fire in the offices of the Capital Gazette newspaper in Annapolis, killing five people and gravely injuring several others.

On his radio show Thursday afternoon, Fox News host Sean Hannity appeared to suggest that Waters was partly responsible for the shooting.

“I’ve been saying now for days that something horrible was going to happen because of the rhetoric,” he said. “Really, Maxine?”

Waters has been subjected to death threats. In April, a San Pedro, Calif., man pleaded guilty to a felony charge of threatening a U.S. official after he called Waters’s Washington office last year and left a voice mail in which he called the lawmaker a racist slur and threatened to kill her. The man, Anthony Lloyd Scott, had called Waters’s office in anger over her criticism of Trump, the Los Angeles Times reported.