More than 4,300 officials have been held accountable for environmental violations in 10 provincial regions after the areas were revisited by environmental inspectors dispatched by the central government to see if problems previously found had been rectified, China’s top environmental watchdog said on July 9.

The inspections, launched in early 2016 and headed by ministerial level officials, had covered all 31 provincial regions on the Chinese mainland as of the end of last year.

At the end of May, the authorities dispatched six teams to revisit 10 of the regions, including Hebei, Henan, Jiangxi and Yunnan provinces. The main task of the teams was to follow up on corrective measures that had been required previously. All the teams completed their work on July 10, the Ministry of Ecology and Environment said.

It also said another 2,819 officials were summoned. About 5,700 companies that committed environmental violations have been fined more than 510 million yuan ($77 million) and 464 people have been detained.

According to the ministry, inspectors received 38,000 tips from the public about violations. As of July 10, local governments had concluded investigations into more than 28,000 of them.

More than 50 of the violations that are considered typical have been made public.

“The exposures work very well to warn and educate the environmental violators,” the ministry said.

Previously, inspection teams publicized problems only after finishing their report. This time, violations were publicized soon after they were discovered.

In one statement, for example, the inspection team criticized the Party committee and government of Qujing, Yunnan province, for failing to rectify problems related to heavy metal waste that polluted upstream parts of the Pearl River.

The city drew up a rectification plan to dispose of 100,000 metric tons of residue containing lead by the end of this year, after an inspection team found in 2016 that about 328,000 tons of residue had been improperly handled.

Revisiting in June, inspectors found the waste that the city promised to deal with had remained untouched, even though the inspection office had sent officials a notification in March urging treatment.

The statement also said special inspectors have been dispatched to watch local rectification work to ensure that reports from the public are dealt with.