An unlicensed fisherman has been fined 3,000 yuan ($494) for electrocuting fish in the rivers and streams of Jiading district, the district prosecutor's office said Monday.

The defendant, surnamed Xie, was accused of illegal fishing for his practice of using a modified battery to electrocute the fish in the water, according to a press release from the Jiading District People's Prosecutor's Office.

Electrocution is an effective, but wasteful means of catching fish, prosecutors said. The practice can kill a large number of fish at one time, but the majority of those fish end up sinking to the riverbed, where they rot and pollute the water. It can also leave surviving fish infertile.

Police and fishery officials caught Xie electrocuting fish on May 9. They confiscated 19 kilograms of fish.

Xie has been caught electrocuting fish out of season on several occasions since he began fishing this way in 2011, prosecutors said. Fishing regulations ban fishermen from electrocuting fish. Violators can be fined up to 50,000 yuan.

Xie was also charged with fishing out of season. The city's government bans fishing from February 16 to May 16 each year to prevent the depletion of fish resources.

According to criminal law, one can be fined or sentenced up to three years in prison for fishing out of season.

Jiading District People's Court gave Xie a light sentence because he confessed to the crimes, said Xu Dan, the court's press officer.