The owner of an indoor fishing pond in Japan burst into tears when he learned that burglars had killed thousands of his fish.

Kazunori Yamada, 48, first noticed on Tuesday, August 2, that a burglary had occurred at the indoor fishing pond in the city of Toki, in central Japan, when he saw a window at the back of the building was cracked and that the door there had been broken.

The burglars stole cash, the WiFi router and the hard drive that contained data from the camera system, according to Tokai TV News One.

But Yamada soon also learned that some 3,000 fish that were being kept in the indoor pond had tragically died during the burglary.

He told Tokai TV News One that the fish died when the burglars cut the power line to the tank's filter system.

"To me, the fish were our company's employees," he said. "My employees were killed. For five years we've cared for the fish, raised them, and now all I can say is I don't know what to do."

"The money we lost and the property damage, honestly, doesn't matter at all compared to [the fish]. It hurts my heart so much that they were killed like this. This is so wrong."

According to Statista, theft and property damage were the most common criminal offenses in Japan in 2020.

It's estimated there were 330.6 reported thefts and 50.8 reports of property damage per 100,000 people, respectively.

Newsweek has contacted officials from the Gifu prefecture for comment on the theft.

While the thousands of fish in Japan were seemingly killed as a result of a criminal act, there have been other instances where Newsweek has reported on the bizarre mass deaths of fish.

Earlier this year, thousands of dead fish washed up on a Staten Island beach in New York, which resulted in many of the residents complaining of a foul stench.

The smell is believed to have been caused by the decomposition of the thousands of fish. A chemical inside fish, called trimethylamine oxide, is responsible for the smell as their bodies decay.

Staten Island has been the location of thousands of dead fish in the past, namely in 2021 when a large number of Atlantic menhaden, known as bunker fish, were located near Great Kills Park.

More bunker fish were found on the shore of Lemon Creek and Wolfe's Pond Park in 2017, where thousands are believed to have died.

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