Horseshoe Falls and Upper Rapids as seen from the Skylon Tower in Niagara Falls, Ontario.
Credits: Bobolink, used under Flickr Creative Commons Attribution 2.0 Generic license
Niagara Regional Police responded at 4:47 p.m. to reports of a woman who plummeted over the massive waterfall.
Const. Nilan Dave said two employees aboard the Maid of the Mist helped recover the body.
Dave said witnesses saw the woman go over the brink.
The woman, in her 50s, was swimming in the Niagara River before she was swept into the water below and likely drowned, he said.
Horseshoe Falls is 57 metres high and empties into the 35-metre deep Lower Niagara River.
Maid of the Mist officials refused to comment.
Foul play has been ruled out. Police continue to investigate.
The woman's identity hasn't been released because police are in the process of notifying next of kin.