Coastguards, police and lifeboat crews spent around half an hour searching Douglas Bay in the early hours of the morning.
A person was said to have gone into the water on Douglas beach at around 12.30am and their friend alerted the emergency services when they didn't reappear.
Douglas coastguards searched the beach while Douglas Lifeboat searched the bay using flares.
Just after 1am, police found the person at home and the search was called off.
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