A county in Nantong, Jiangsu province, suspended operations at 28 chemical factories after parents said pungent emissions had sickened their children.

The case follows the sickening of hundreds of students at another school in the province recently.

Since mid-April, many parents of children at Hai'an Chengnan Experimental Elementary School, located near the plants, have complained that their children experienced nosebleeds, skin rashes and coughs.

"My daughter keeps saying that the air at the school smells funny and her nose is itching," said Li Caixia, the mother of a 9-year-old.

"Many parents gathered in front of the school to protest the air pollution," she said. "I'll stop sending my child to school if the air quality doesn't improve."

According to the online news outlet ThePaper.cn, more than 20 of the 50 students in a second-grade class have shown symptoms of health problems.

On Monday, representatives of parents met with the head of the elementary school and urged the school to solve air quality problems.

"We want the environmental protection bureau to monitor the air quality on a daily basis," said Yue Qiuyi, a mother whose daughter attends second grade. "The government should make it clear to us whether the symptoms are connected to the air pollution."

The local government has formed 23 teams to inspect the 28 chemical factories and make sure they have stopped production as ordered.

A professional inspection company has also been invited to test the air. The results will be released to the public as soon as possible, the government said.