Agriculture officials in Hainan have been accused of trying to suppress evidence that genetically modified crops have been grown illegally on the southern island province.

Allegations that several companies and research institutions have carried out illegal GM corn and cotton trials in Hainan emerged on the Internet late last month.

On Sunday, the provincial agricultural department confirmed that 15 crop samples taken around the cities of Sanyan, Lingshui and Ledong tested positive for genetic modification.

Nine samples have been destroyed and investigations are continuing into the six others.

The department said checks took place between December 23 and 27.

However, officials didn't reveal the findings until accounts went viral on the Internet, leading to claims of an attempted cover-up.

One Weibo microblogger asked: "Are there any other cases that you haven't told us about?"

Commercially sensitive

The department hasn't responded to the public accusations, but promised to strictly implement GM safety management rules.

An official with the department's technology education section said it was "inconvenient" to reveal commercially sensitive information, the Legal Evening News reported yesterday.

China's State Council issued safety regulations in 2001 regarding the introduction, trials and circulation of GM food.

Under the regulations, crops that have not received permission are banned.

Concerns about GM crops have been making the headlines in China recently.

Last month, former television talk show host Cui Yongyuan claimed the country's consumers are unwittingly eating GM crops that are grown illegally on a large scale.

Also last month, eminent agricultural scientist Yuan Longping - renowned for developing high-yield rice strains - told a forum in Beijing that special attention must be paid to disease- and pest-resistant GM strains.

Yuan asked: "If pests die after eating these foods, what will become of the human beings who consume them?"