A rescue operation was triggered in the northern German city of Hamburg on Sunday after a jogger spotted what he thought was a drowning person.

The local fire department deployed several boats, a helicopter and a diving team to the cool waters of the Elbe River. An ambulance and the police were also at the scene.

But they were unable to find any trace of the struggling swimmer, following the reports of someone struggling to swim near the Teufelsbrück (Devil's bridge) jetty.

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The jogger who had left the scene was asked to return to pinpoint exactly where he had spotted the flailing person. But no human could be found.

Happy ending

Instead, rescuers found a seal happily splashing around in the water.

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The mammal appeared repeatedly and seemed to be watching the rescue operation unfold, the Hamburg Morgenpost reported.

Sunday's incident wasn't the first time that seals were spotted in the northern port city this year.

Several other sightings have taken place on the shores of the Elbe, which one local animal shelter explained was often due to pup seals getting separated from their mothers.

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