Republican presidential candidate Donald Trump speaks to supporters at a...

Republican presidential candidate Donald Trump speaks to supporters at a campaign rally Saturday, Nov. 28, 2015 at Robarts Arena in Sarasota, Fla. Credit: AP / Steve Nesius

A journalists' association has demanded that GOP front-runner Donald Trump apologize for mocking a New York Times reporter's handicap.

The New York Press Club slammed the billionaire real estate developer-turned-White House hopeful for imitating the hand gestures of Serge Kovaleski -- who has arthrogryposis, a condition that limits joint function.

"There is a time-honored tradition of politicians sparring with journalists," said the club's president, Steve Scott, of WCBS NewsRadio 880, in a statement Saturday. "But, Mr. Trump has crossed a line. His onstage imitation of Mr. Kovaleski, which included the use of jerking arms and an affected voice, is an insulting personal attack that simply cannot be condoned."

Kovaleski wrote a 2001 story while at The Washington Post, cited by Trump, reporting that authorities detained several people in New Jersey who were allegedly celebrating the downing of the Twin Towers. Kovaleski's article did not say that thousands were celebrating -- or that the allegations were true. Kovaleski recently said that his reporting never bore out that thousands, or even hundreds, were celebrating. Trump's claims about thousands of celebrating Muslims on 9/11 have been widely debunked.

At a rally after Kovaleski's recent statement, Trump ridiculed the reporter.

Under fire for mocking disability, Trump claimed he couldn't be making fun of Kovaleski's condition because Trump didn't know the reporter. Kovaleski, though, said the two were on a first-name basis following interviews for the New York Daily News, including in the developer's own office and aboard Trump's jet.

Neither Kovaleski nor Trump could be reached for comment Saturday.

NewsdayTV's Doug Geed visits two wineries and a fish market, and then it's time for holiday cheer, with a visit to a bakery and poinsettia greenhouses. Credit: Randee Dadonna

Out East with Doug Geed: Wine harvests, a fish market, baked treats and poinsettias NewsdayTV's Doug Geed visits two wineries and a fish market, and then it's time for holiday cheer, with a visit to a bakery and poinsettia greenhouses.

NewsdayTV's Doug Geed visits two wineries and a fish market, and then it's time for holiday cheer, with a visit to a bakery and poinsettia greenhouses. Credit: Randee Dadonna

Out East with Doug Geed: Wine harvests, a fish market, baked treats and poinsettias NewsdayTV's Doug Geed visits two wineries and a fish market, and then it's time for holiday cheer, with a visit to a bakery and poinsettia greenhouses.

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