BEIJING, April 29 -- Beijing police announced on Tuesday that a month of a campaign against illegal activities including prostitution in rentals has snared hundreds and punished rental owners.

The "clean community" campaign started in early April. A total of 144,400 rental houses have been checked and 401 law breakers, including 39 engaged in prostitution, detained, a statement by Beijing's Public Security Bureau reads.

According to the statement, Beijing police also found 16 pieces of combustible articles or explosives and 265 controlled knives in the campaign.

It says that 108 rental owners have been punished, noting rental owners should report tenants suspected of committing crimes to the police. Otherwise, the owners will be punished.

In 2013, Beijing police received more than 1,000 reports of prostitution in rentals, accounting for 25.2 percent of such cases in the city. The prostitution in rentals hampers greatly the safety and stability in the community, the statement reads.