The search for a 19-year-old woman who fell into the Niagara River and was swept over the falls on Sunday evening is being scaled back.

On Monday morning, divers and searchers from a handful of agencies, including the Niagara Regional Police, the Niagara Falls Fire Department and the Niagara Parks Police, searched the area below the falls, but couldn't find the woman, who is presumed to have drowned.

Search crews instead found male remains in a whirlpool of the lower Niagara River, but police said there is no connection to the missing student.

At a Monday afternoon news conference, the Niagara Parks Police announced the search was being scaled back with little hope left of finding the woman alive.

The woman's name was not released but police said she was a 19-year-old exchange student from Japan studying in Toronto.

Niagara Parks Police said two young women were visiting the falls around 8:30 p.m. ET Sunday.

One of the women sat on a pillar at Table Rock, located about 24 metres upstream of the falls on the Canadian side, to pose for a photograph. Police say the woman's legs were straddling the railing and she lost her footing after standing up.

She fell into the river and the swift current quickly swept her over the falls.

"It would appear that this is a tragic accident by misadventure, with fatal consequence," said a news release from the Niagara Parks Police.

A warning sign on the barrier not far from where a woman fell on Sunday evening. Jon Castell/CBC News

Police said the woman's fall was captured on surveillance cameras at the popular tourist spot.

There was no one in the immediate area of the fall and foul play is not suspected, police said.

Scaling the railing is "clearly dangerous and prohibited," but visitors do it every day, said Niagara Parks Police Chief Doug Kane.

Still, the police chief said it's the first time he has heard of a tourist tumbling off the edge in that spot.

"We get about 11 million people a year here who view that annually — this is the first occurrence of this nature that I can recall," said Kane, who has worked in the region for 35 years.

In another incident on Sunday, a 27-year-old man survived an almost 10-metre fall down the Niagara Gorge.

The man, from London, Ont., had to be extricated from the gorge by fire officials and was sent to hospital with a broken leg and head trauma.

Police said he would be charged under the Niagara Parks Act of Ontario.

With files from The Canadian Press