Buildings are blanketed in heavy smog near Guomao Bridge in Beijing, capital of China, Oct. 28, 2013. According to Beijing environment monitoring data, the air quality of central area and southern parts of Beijing is heavily polluted from Sunday night to Monday. (Xinhua/Luo Xiaoguang)

China's environmental watchdog said on Tuesday that it dealt with 179 tip-offs on environmental pollution in July, marking a 20 percent jump compared with the number in June.

Of the processed tip-offs, 155 were about environmental illegalities, accounting for 87 percent of the reports, according to the Ministry of Environmental Protection.

The environmental watchdog in north China's Hebei Province received 22 tip-offs, making it the province with the highest number of complaints. It was followed by the provinces of Shandong, Jiangsu and Guangdong, said the ministry in a statement.

All the complaints have been transferred to local environmental watchdogs for further investigation, the statement added.

Some 101 of the total 179 tip-offs in July were related to air pollution, 31 were about water pollution and 28 were about noise pollution. The others concerned solid waste pollution and construction projects that had not been properly approved.

In 57 cases, companies were asked to correct the problems, while in 39 cases, businesses were suspended to allow for pollution control. In 33 other cases, businesses were fined, and in another 14 cases, projects were canceled or businesses were closed.

In the city of Taiyuan in north China's Shanxi Province, a magnesium production company was ordered to stop production until it builds necessary pollution control facilities.