Police in Beijing detained almost 40 people connected to 30 cases involving illegal possession of guns in a month since a special operation targeting banned firearms started in March.

The Municipal Public Security Bureau said in a statement today that the number of the cases increased by 36 percent compared to the same period last year.

Thirty-seven suspects were taken into custody, a year-on-year increase of 19 percent, the bureau said.

One of the cases involves four people detained for using improvised firearms to a game called Counter Strikes.

The police encouraged the public to report any possession of firearms, including Airsoft guns and shotguns, with rewards ranging from 5,000 yuan ($770) to 10,000 yuan.

Private possession of firearms in China is strictly prohibited with very limited exceptions.

Firearms for civilian use are usually permitted for specified organizations and workplaces, such as in certain sports hunting, protection, breeding and research of wildlife.

Hunters in hunting areas and herdsmen in pastoral regions may be allowed to possess hunting rifles.