The unidentified 911 caller told the dispatcher at 1:49 p.m. that the victim, identified only as a 77-year-old male, suffered "serious bleeding" and that the fall was "accidental".
New York Rep. Peter King said he had "some differences" with Ailes but that doesn't diminish his impact on news and politics.
Few other details were immediately available, including whether the victim was taken to the hospital.
Hannity praised Ailes for his insight and acumen, saying that the former Fox News chief "was always the strategist".
Mr Ailes ran Fox News for two decades and is credited with transforming it into arguably the most powerful voice in conservative media.
In death, Roger Ailes has become a talking point for the kind of polarization and loathing he spent his career fomenting, a fitting legacy for one of the culture wars' biggest instigators. "Roger was a great patriot who never ceased fighting for his beliefs".
Rupert Murdoch, executive chairman of 21st Century Fox and Fox News Channel, said he was saddened by the development.
Brian Stelter, in a voiceover on CNN about Ailes' death, said Fox News made politics a "permanent campaign, lifting up Republican candidates and conservative policies". Carlson said she was sacked for refusing Ailes' sexual advancements, and Tantaros alleged Fox News was "steeped in intimidation, indecency and misogyny".
Last July, Ailes resigned from Fox News under pressure from Murdoch amid multiple sexual harassment allegations against him.
On "Fox & Friends" Thursday morning, co-host Ainsley Earhardt choked up as she shared an emotional reflection: "Many people out there would say that he saved this country by starting the Fox News Channel". More recently, he worked on debate preparations in the presidential campaign of now president, Donald Trump.
Ailes was sacked from Fox News past year after he was accused of sexual harassment by more than 25 women. In a second tweet, he relayed that, "Per 2nd family friend on cause of death: Ailes fell in Palm Beach and had a blood clot from the fall".
Nixon would later invite Ailes to travel from Media, Delaware County, where he lived at the time, to NY, where, Ailes told the Inquirer, "Nixon's staff grilled me for three hours".
In 1996, Ailes helped launch Fox News, which dramatically changed the media landscape. More women came forward with their stories, which left Murdoch no choice but to fire Ailes during the scandal.
Our thoughts and prayers now turn to him, his Wife Beth, his son Zachary, his brother and his family.