On Feb. 24, four passengers were forbidden to board a plane in eastern Hangzhou city after one of them joked at the check-in desk that his partners were terrorists.

A passenger surnamed Li is alleged to have told the check-in clerk to beware of the three men following him before the plane was due to depart at 9:00 p.m.

"Take care and do not let them in. They are terrorists," he allegedly said, ignoring the clerk's warning that he would be held responsible for his words.

The four men, all from the eastern Zhejiang Province, were heading to Guangzhou, capital of Guangdong Province, to sell shoes. The other three were surnamed Zheng, Lu and Yu, according to the airport police.

The four were taken to the public security office for questioning and missed their flight. The airport police fined them after establishing they posed no security risk.

Under China's law on administrative penalties for public security, those making false reports of danger and disease can be detained for five to ten days, and fined a maximum of 500 yuan (US$69).