Ninety people have been sent to hospitals since Saturday in a city in east China's Jiangxi Province after industrial gas leaked out of a chemical plant, hovering parts of the city for three hours, local government officials said Sunday.

But the officials did not disclose the conditions of the patients, many of whom complaint their eyes were hurt.

The acid industrial gas with a pungent odor burst out from the pipes of a chemical plant in the hi-tech park of Xinyu City at about 5 p.m. Saturday. Some of the nearby residents felt their eyes hurt by the spill and others were panicked and rushed out of the city, Xinyu's publicity officials told reporters.

The spill was stopped by 8 p.m. Saturday, officials said, adding that Qianwei Chemical Co., Ltd did not report the accident in time and caused a delay in the emergency response.

Officials said the latest environmental tests, conducted early Sunday morning, showed that Xinyu's air quality was normal. Residents who fled during the spill are returning, they said.

The authority is still probing the case and has vowed to punish those who are found responsible.