A man has survived after going over Horseshoe Falls in Niagara Falls, Ont., one of only a handful of people ever to survive such an experience, says the chief of the Niagara Parks Police.

Chief Douglas Kane told ctvtoronto.ca on Wednesday that he thinks this is only the third time this has happened, with the last incident coming almost six years ago.

Fatalities are much more common, he said.

The drama began at 2:11 p.m. when a witness saw a man, believed to be in his mid-30s, crawl over a wall and enter the rapids of the Niagara River. He went over the world-famous Horseshoe Falls, about a 56-metre drop, and ended up in the river below.

"I was on the very edge of the Canadian side ... and he was right next to shore, like a metre away from it, and he just went overboard. He wasn't resisting it at all," said eyewitness Konstantine Shatalov, who added the whole sequence of events didn't seem real to him.

When the man emerged below the falls, the force of the current had pulled off his clothes.

Oshawa resident Phillip Richmond, who was returning from a trip to Florida, took some photos and passed them along to CTV Toronto.

"He was swimming and he kept swimming away from shore, so it looked like he was either being a daredevil or there was some other problem," he said.

Rescue teams involving several Niagara emergency agencies went to attempt to extract the man, "but he swam away further into the river," Kane said.

"He was floating in a cyclic kind of rotation," which meant he went downstream, but then circled around and stayed out of rescue range, Chief Lee Smith of the Niagara Falls Fire Department told reporters. "But he didn't appear to want our help."

Smith added this observation: "We're amazed he stayed up as long as he did."

A private helicopter used the air washing down from its main rotor to push the man closer to shore. A Niagara Falls firefighter, tethered to shore and wearing a dry suit, went into the river and extracted the man, Kane said.

The individual was apparently feeling the effects of hypothermia after being immersed in the river's cold waters for almost 45 minutes. He was semi-conscious when rescuers pulled him from the river about 300 metres down from the falls, he said.

Paramedics took the man to Greater Niagara Hospital for treatment, he said.

The man also suffered a head injury.

Kane said officers will attempt to identify and interview the man once he's been treated and recovers from his experience.

With a report from CTV Toronto's John Musselman