A man survived a 180-foot plunge over Niagara Falls on Monday, becoming only the fourth person to do so without any protective devices, according to news reports.

The man, who has not been identified, climbed over a retaining wall above the Canadian Horseshoe Falls before jumping into the Niagara River and being swept over the falls, according to a report from CNN affiliate CTV.

Thought to be around 40 years old, the man sustained injuries including several broken ribs, a collapsed lung and gashes to his head and shoulders, according to a report in the Buffalo News.

He was pulled to safety by emergency crews on the Canadian side of the river after collapsing in waist-deep water, according to a report from CNN affiliate WGRZ in Buffalo.

"When I first looked at him, it was quite apparent that he was in a state not only of shock, hypothermia had probably started to set in," Sgt. Chris Gallagher of the Niagara Falls Parks Police told WGRZ.

"He just happened to come down the river into an eddy, and that enabled him to get out. If he had been in the main current, he wouldn't have survived," Niagara Falls, Ont., Fire Department platoon chief Dan Orescanin told the News.

The man was in stable condition at Hamilton General Hospital in Ontario on Tuesday morning, according to a report from the CBC.

On Tuesday morning, New York State Park Police said they'd received a report on a second person going over the falls, this time the American Falls, the Buffalo News reported.

Lt. Patrick Moriarty said they were interviewing witnesses and believe it was a suicide attempt, the News reported.

The man who survived on Monday is only the fourth person to survive a plunge over the Horseshoe Falls, historian Paul Gromosiak told the News.

The others include a 30-year-old Canadian man in 2009, a Michigan man in 2003 and a 7-year-old boy in 1960, according to the news reports.

"There are odds that you will survive, but they're so minuscule that it's impossible to comprehend," Gromosiak told the News. "Out of the thousands who have come here to commit suicide over the years, we have two who did survive."

Monday's incident had not yet been labeled a suicide attempt, according to the reports.

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