BEIJING, Aug. 5 -- China has imposed punishment in 25,164 environmental violation cases in the first half of 2015, with 9,325 companies having their doors sealed, the Ministry of Environmental Protection said Wednesday.

Violators were fined more than 230 million yuan (37.6 million U.S. dollars), and 740 cases of suspected environmental crime have been transferred to the police for criminal investigations.

Since the Environmental Protection Law took effect this year, environmental authorities have closed down companies, limited or suspended on production, and detained wrong-doers.

The ministry has given administrative punishment to ten cities, and people in charge of polluting companies in four of the ten were warned or sacked.

The ministry said it will cooperate with other ministries to tighten environmental inspection with increased awareness from local governments, enterprises and the public.