Rally attendees display their feelings for the media before Donald Trump’s speech on Oct. 13 in Cincinnati. (Ty Wright/Getty Images)

Donald Trump’s rallies have never been the friendliest places for reporters. But lately, as Trump has come under increasing fire, an unwelcoming atmosphere for the press has turned into outright hostility.

Reporters who cover Trump on the campaign trail say his supporters have become more surly and abusive in the past week, egged on by a candidate who has made demonizing journalists part of his stump speech.

Trump’s traveling press contingent of about 20 has been met with boos, shouts and obscenities as it entered — as a single group — the venues where Trump has spoken this week. One reporter who is part of the traveling group described it as “a mob mentality,” particularly at larger rally sites.

“We’ve been on the receiving end of that throughout the election, so we’ve largely become numb to it,” he said. “But in the last few days it’s just been so much louder, so much angrier. The people who are shouting look at us like we’re their immediate enemies, not as like . . . primarily late-20-to-early-30-somethings there to do a job.”

At Trump’s rally in Cincinnati on Thursday, the crowd chanted, “Tell the truth!” as reporters trooped into the designated pen that the campaign has long used to corral reporters. Another recurring chant this week: “CNN sucks!”

Republican presidential nominee Donald Trump called the election – and the American political system – "one big fix" at a rally on Oct. 14 in Greensboro, N.C. (The Washington Post)

Some 15,000 Trump supporters showered the small group with prolonged boos and heckling during the Cincinnati rally. Several people approached the press barrier to yell directly at the group and to make obscene gestures, “which has made a lot of people uncomfortable,” according to one journalist.

Reporters are now concealing or removing their press credentials when leaving the pen to avoid confrontations with Trump’s supporters. The atmosphere is particularly threatening to female reporters and to female TV reporters whose faces are well known, reporters say. (“The camera draws the hate,” as one put it.) Some reporters have wondered aloud about the need for more security, or at least more barriers to separate them from the crowd as they enter and exit Trump’s events.

Another reporter, who asked not to be named because his publication restricts staff members from commenting publicly, said he left the pen on Thursday with another reporter “because we didn’t want to go out into a sea of 15,000 people alone.” They were approached by a young man who started shouting at them to tell the truth and pointing his finger in their faces.

“It was the sort of moment that could have escalated very quickly if we had responded,” he said. Instead, they ignored the man and kept walking.

Several journalists attributed the increasingly chilly climate to Trump’s stepped-up criticism of the media.

BuzzFeed political reporter McKay Coppins said Republican candidates have long been skeptical of the news media, and “some of their criticism has merit.” But, he added, “what Trump’s doing seems different. He’s trying to convince his followers that reporters are not just unfair or incompetent, but part of some kind of sinister global conspiracy. I covered the Romney campaign in 2012, and we heard plenty of gripes about press bias, but we weren’t walking into arenas with thousands of people angrily booing and heckling us while we worked.”

On Thursday, Trump said the news media was part of a “global conspiracy” working in concert with Hillary Clinton to destroy his candidacy. He kept it up Friday, denouncing reports that he had sexually assaulted women as “lies” and saying, “the corrupt media is doing everything in their power to stop this movement.”

He singled out reporters at the New York Times as “corporate lobbyists” for Mexican billionaire Carlos Slim, a leading shareholder in the Times’ parent company, and Clinton. (The Times reported this week on two women who accused Trump of inappropriate contact.)

Trump has had one of the most contentious relationships with the press of any major candidate in memory. In addition to confining reporters to pens at his rallies, he has banned as many as a dozen news organization at various times in the past 15 months. He has also threatened, if elected, to “open up” libel laws to make it easier for public figures like him to sue news outlets whose reporting displeases him.

“There’s been an escalation in the rhetoric about the press, that there’s a vast conspiracy, and it’s something the crowd has absorbed,” said Ben Schreckinger, a reporter for Politico. “It seems to have made the crowds more aggressive and angry.”

Schreckinger was booted out of a Trump rally in June and returned to cover the candidate’s events only this week. The difference was noticeable, he said: “In the past, when Trump incited the crowd against the press, you could see people smiling and laughing as they were booing. It was like the mood of a crowd at a ballpark. Now the smiles have disappeared.”

Trump’s campaign did not respond to a request for comment.