Hokkaido sees rare phenomenon of sea ice heading upriver

An unusual phenomenon has surprised people in the coastal city of Abashiri in Japan's northern island of Hokkaido -- sea ice heading up a river toward a lake.

Footage taken last Wednesday by an NHK camera crew shows ice floes covering the surface of the Abashiri River about 4 kilometers upstream from its mouth.

The season's first drift ice had reached the coast two days earlier from the Sea of Okhotsk.

By Monday, the ice floes had reached entrance of Lake Abashiri.

Officials at the Hokkaido Regional Development Bureau's Kitami River Office say the sea ice around the port was likely pushed upriver when the tide was high.

The officials say there is no record of such a rare phenomenon in recent years. It certainly surprised Abashiri residents, who are otherwise used to seeing the arrival of sea ice.

A man who runs a seafood shop near the river said he has lived in the city for a long time but had never seen anything like it before. He added that his post on social media about the ice floes got a lot of reactions.