President Trump doubled down Thursday on blaming the media for the nation’s incivility, as suspicious packages sent by a suspected serial bomber continued to target Trump’s outspoken critics.

“A very big part of the Anger we see today in our society is caused by the purposely false and inaccurate reporting of the Mainstream Media that I refer to as Fake News,” the president said in a morning tweet. “It has gotten so bad and hateful that it is beyond description. Mainstream Media must clean up its act, FAST!”

Trump’s tweet — which prompted sharp criticism from Democrats — was sent amid television coverage of police in New York swarming a block in Lower Manhattan after receiving reports of a suspicious package at a building where actor Robert De Niro has offices. The package was addressed to De Niro, who attacked Trump in June during a profane presentation at the Tony Awards.

Investigators later found a package addressed to former vice president Joe Biden in a Delaware mail facility that was like the other pipe bombs found this week, according to a law enforcement official.

Trump also took aim at the media on Wednesday night, speaking at a political rally in central Wisconsin after a string of homemade bombs were sent to former secretary of state Hillary Clinton, former president Barack Obama and others.

During the rally, Trump was relatively subdued as he spoke, interrupted himself several times to point out that he was “trying to be nice” and took no responsibility for his own role in contributing to the country’s degraded civic discourse.

“The media also has a responsibility to set a civil tone and to stop the endless hostility and constant negative — and oftentimes, false — attacks and stories,” Trump said at the rally.

In an apparent swipe at Democrats, Trump also denounced those who “carelessly compare political opponents to historical villains” and who “mob people in public places or destroy public property.”

The president has long made the media a target of his ire, denouncing reporters as the “enemy of the people.”

The targets of suspicious packages in recent days have all been derided by Trump as well. After De Niro attacked him in June, Trump fired back on Twitter, calling him a “very Low IQ individual” who had taken “too many shots to the head by real boxers in movies.”

One of the undetonated devices was found Wednesday at CNN’s New York headquarters. It was addressed to former CIA director John O. Brennan. Since leaving the government, he has been an outspoken critic of Trump; he is an on-air analyst for NBC News and MSNBC, rather than CNN.

On Thursday, Brennan responded to Trump’s tweet with a scathing tweet of his own.

“Stop blaming others,” Brennan said. “Look in the mirror. Your inflammatory rhetoric, insults, lies, & encouragement of physical violence are disgraceful. Clean up your act. . . . try to act Presidential. The American people deserve much better. BTW, your critics will not be intimidated into silence.”

Sen. Chris Murphy (D-Conn.) also condemned the president’s tweet.

“Rise up, America,” he said on Twitter. “The President of the United States is now blaming the attempted murder of Democrats on press criticism of him. I didn’t think his narcissism could sink to this ugly of a place. But it has.”

Sen. Chris Van Hollen (D-Md.) credited Trump for calling for unity during remarks about the pipe bombs made at the White House on Wednesday afternoon. But Van Hollen said that moment was “fleeting.”

By Wednesday night, “he was at a rally blaming everybody but himself for this toxic political environment we find ourselves in,” Van Hollen said in a CNN interview.

“Everybody needs to do their part here,” Van Hollen said. “When the president went to the rally last night, he didn’t do his part.”

During an interview Thursday morning on Fox News, White House press secretary Sarah Sanders stressed that Trump has condemned the actions of the suspected bomber and said that he “could not have been more presidential” in addressing the crisis on Wednesday.

Asked by a Fox News host if Trump could go “the extra mile” to foster more civil political discourse, Sanders said: “Look, the president did exactly that last night.”

She argued that Trump has an obligation as president to point out differences in policy between the two major political parties.

“There is a major political, philosophical difference between Democrats and Republicans, and there’s nothing wrong with pointing those differences out,” Sanders said. “There is something wrong with taking that to a point of violence.”

Sanders also pushed back on a stinging statement by CNN World President Jeff Zucker hours after the package sent to Brennan led to the evacuation of the network’s staff from the Time Warner Center in Manhattan.

“There is a total and complete lack of understanding at the White House about the seriousness of their continued attacks on the media,” Zucker said. “The President, and especially the White House Press Secretary, should understand their words matter. Thus far, they have shown no comprehension of that.”

On Thursday, Sanders said she found it “absolutely disgraceful that one of the first public statements we heard from CNN yesterday was to put the blame and the responsibility of this despicable act on the president and on me personally when the person who is responsible for this is the person who made and created and put these suspicious packages in the hands and in the arms of innocent American citizens.”

Josh Dawsey and Felicia Sonmez contributed to this report.