Image copyright Sina Weibo Image caption The original report on China's state news broadcaster was unusually outspoken

Investigators in China say they have found no evidence that pollution caused hundreds of school pupils to become sick earlier this year.

State TV in April said soil tests near the school showed chemical levels at 95,000 times the national limit.

But a three-month study of the air, water and soil around the school said contamination levels were within acceptable limits.

It did not say what might have caused the children's sickness.

The Changzou Foreign Language School in Changzhou, Jiangsu province, was built near recently-closed chemical plants.

In its report in April, state broadcaster China Central Television (CCTV) said that 500 children had developed dermatitis, blood abnormalities, leukaemia and lymphoma, and nearly five out of six pupils who underwent medical checks had health problems.

The report was viewed online by tens of millions of people and caused outrage across the country.

Other news outlets reported that the school had been built against the advice of environmental regulators.

Changzou city officials have told the official Xinhua news agency there were "some problems with the earlier soil rehabilitation process" but said that otherwise the investigation found few significant problems.

They said there was no link between the school's location and thyroid problems the pupils had been having, adding that the rate of thyroid problems was rising in the general population.