A search and rescue crew is looking for an Alberta man who disappeared over a waterfall in Jasper National Park, but say hope is fading that he will be found alive.

The 25-year-old man was hiking with a friend when he slipped into the river and went over Athabasca Falls Thursday night.

It's a tragedy and our hearts go out to the friends and family," said Steve Blake, Visitor Safety Manager.

"Our efforts last night were to try and find someone who could have possibly survived; today it's not too likely."

Blake says kayakers and swimmers, as well as a helicopter, searched for the man until midnight Thursday.

Air and water searches continued Friday.

"We'd love to be able to .... provide closure for the families and ...that's where our efforts will be today."

Blake says the last time someone went over the falls was in 2006.