1200 tons of fish washed up on a Japanese beach and nobody knows why

• About 1,200 tons of fish washed up on a beach in Hakodate, Japan, per AP.
• City officials said in a statement that the cause was still unknown.
• The fish may have been chased by bigger fish and died of suffocation, one researcher told AP.

An estimated 1,200 tons of fish have washed ashore on a Japanese beach — and local officials are struggling to explain why.

According to the Associated Press, the volume of sardines and mackerel found floating off the city of Hakodate, in the northernmost of Japan's main islands, was such that it extended across more than 0.6 miles, per officials.