BEIJING –

China's vice minister for environmental protection has announced a two-year inspection campaign to root out fake air quality data and accused some local governments of manipulating the data to meet national standards, state media said.

The move comes as China has sought to improve transparency and compel polluters to provide comprehensive emissions data in real time. Air pollution is one of the top items on the government's agenda since a choking smog dubbed the "airpocalypse" engulfed key Chinese cities in January 2013.

Some local governments make monitoring stations fabricate or tamper with air quality data, state news agency Xinhua quoted Wu Xiaoqing, vice minister of environmental protection, as saying.

Wu said that such acts severely compromise the credibility of the government and environmental protection agencies and harm environmental monitoring efforts.

"Guaranteeing the truthfulness of the data is the bottom line," Wu said, according to Xinhua.

Monitoring stations directly affiliated to the ministry would help check data from other stations, Wu said.

Beijing has declared a war on pollution, vowing to abandon a decades-old growth-at-all-costs economic model that has spoiled much of China's water, skies and soil.

A study by Greenpeace and scientists at Peking University based on 2013 data attributed more than 257,000 premature deaths in 31 Chinese cities to PM2.5 — microscopic pollutant particles in the air — making it a bigger killer than smoking.

On Monday, Beijing introduced measures to limit the number of motorists on heavily polluted days, the latest move by authorities in the Chinese capital to battle the choking smog that has blanketed the city in recent years.

Under China's newly amended environmental law, criminal penalties will be imposed on those found guilty of trying to evade pollution monitoring systems.