The search for a man who fell off a of a cruise boat in Lake Ontario on Saturday night and disappeared has wrapped up for the night without any sign of the man.

“Because of the change in water clarity as well as debris in the water, we had to conclude our search for today,” Sgt. Eric Goodwin of the Toronto Police Marine Unit told CP24 Sunday night.

Goodwin said poor weather conditions hampered the search Sunday, with rain sending an increased volume of water jutting into the lake from the Humber River.

“We have done an extensive amount of searching to date and still we have negative results,” Goodwin said.

He said the search would resume at a later point.

Earlier in the day police said they didn’t “want to give up hope” that a positive outcome could still be realized.

Officers with the Toronto Police Marine Unit scoured an area about two miles south of the Humber River as they continued their search.

The man, believed to be in his 20s, fell off the back of the 'Northern Spirit’ at around 7:40 p.m. on Saturday during a party. Other passengers on the boat were initially able to track the man, but he eventually vanished.

The temperature in Lake Ontario was about 9 C at the time the man disappeared. At that temperature, Hypothermia can set in within 10 minutes.

"We currently have two boats in the water and we are just continuing with the search. We started at about 7:30 a.m. this morning and we will go for as long as we can," Sgt Gerry Klunder told CP24 on Sunday morning. "It is a large area and due to the time frame that it happened – it is 13 hours ago now – and with the current that comes out the Humber River it makes it (the search) much more difficult."

According to a notice about the cruise party posted online, the sunset event featured dinner, DJs, a live band and access to three bars aboard the three-storey yacht.

The cruise began at around 6 p.m. and was expected to go until 8:45 p.m.

“Our hearts are with the family and friends of the young man and at this time we are cooperating fully with the police investigation as it goes on,” Mariposa Cruises CEO Jim Nicholson told CP24 on Sunday. “We place safety at the foremost in our company. We have been around for 29 years and we have never had an experience like what we had last evening. I can’t tell you how sad we are for the family and everyone surrounded by it.”

According to Nicholson, there were about 427 people on board the boat the time the man disappeared as well as 19 crew members and 10 security guards.

The boat was licensed to carry 550 people.

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