Authorities will severely punish government officials who abuse their power to cover up environmental crimes, the Supreme People's Procuratorate said on Thursday.

"To protect the economy and obtain a good GDP performance, some local governments and law enforcement officers have covered up crimes or reduced punishments," said Li Zhongcheng, deputy director under the procuratorate's malfeasance and infringement investigation department.

From March to April, national prosecuting departments authorized public security organs to investigate 228 cases of illegal acts that harmed the environment, a year-on-year increase of 10.1 percent, according to the procuratorate.

During that period, national prosecutors charged 3,309 suspects in connection with 2,158 cases, a 14.4 percent increase.

Most of the investigated officials worked in environmental protection, forestry, water conservation and public security sectors, and they allegedly took bribes to not report or punish environmental protection laws violators, Li said.

"Some of them allegedly neglected their duties to indulge polluting emissions and abused their power to approve polluting projects," he said.

Some went so far as to conspire with suspects and accept bribes to facilitate pollution projects, while canceling or reducing sewage charges and relevant fines at random, causing great losses to the economy, he said.

According to the procuratorate, official dereliction of duty and malpractice in ecological and environmental protection caused 25 deaths, 12 injuries and 3.1 billion yuan ($498 million) in economic losses in 2013.

"Serious environmental damage caused by such crimes can't be repaired in the short term," Li said.

Yuan Ming, deputy director of the procuratorate's investigation and supervision department, said the enterprises involved should be blamed for serious incidents of pollution.

"Their legal awareness is relatively weak, and to cut costs and reap high profits, they failed to install equipment to filter polluting particles and discharged the pollution at will," he said.

Practical difficulties arise in handling such crimes, Yuan said, adding that it's difficult to identify the victims or find witnesses or informants in pollution-related crimes.

It's also hard to obtain evidence. "In many cases, when we find a clue, the polluted water source has been diluted, and it's difficult to identify the level of the pollution and the toxic elements," Yuan said.

Prosecuting departments will intensify supervision of environmental protection and public security sectors, and report crimes and punish wrongdoers in a timely manner, Yuan said. He added that further action will be taken to weed out officials who abuse their power to provide "protective umbrellas" to criminals.

Hong Daode, law professor at the People's University of Political Science and Law, said the criminal law on ecological and environmental protection is lagging behind that of other countries.

"We should upgrade the laws to clarify different crimes and sentencing standards, and exert more criminal punishments," he said.