NANJING -- A man suspected of sexually assaulting and killing a seven-year-old girl in east China's Jiangsu Province has been caught, police said on Wednesday.

The man, surnamed Wang, who allegedly kidnapped and sexually assaulted the girl on Friday, has been captured by police in Qiaotou Town of Jiangyan District, Taizhou City, according to the city's public security bureau.

The police said the suspect did not know the girl and his motive is still unknown.

The girl, a resident of Yangzhou City, went missing in a village in Taizhou City when she and her grandmother attended a relative's wedding ceremony there, said a spokesman from the bureau.

Her body was found at a nearby riverside on Monday. Further investigation is under way.

The case has shocked netizens in China. "How cruel the man is. Why did he kill an innocent girl? I want to know the reason," said a web user posting under the name Haituntutu at Chinese microblog site Sina Weibo.

"How to prevent such tragedies from happening again? It is a question schools and parents need to discuss together," said another Weibo user under the screen name Ouchen.