A three-month investigation and DNA technology helped police rescue three kidnapped children and apprehend four suspects in their abductions, the Dongguan Public Security Bureau said Thursday.

All three children, two boys and a girl, are from rural Dongguan, south China's Guangdong Province. They were found separately on April 15 and April 26 and Sunday in Guandong and Hunan, police said.

"All the children were sent back to their parents, after DNA verification," said a policeman who didn't give his name.

The three were among several children aged six months to three years who have been kidnapped in broad daylight from rural Dongguan. Police said they don't know exactly how many children have been kidnapped.

Police made their first arrest on April 15, when they apprehended a 28-year-old male suspect surnamed Lu. They caught three other suspects between April 15 and April 27.

The police told Xinhua that there have been six reported kidnapping cases in 2009. So far, four children have been recovered.

Police in central China's Anhui province are aggressively searching for the kidnapped children, with the help of DNA labs in the province.

China's Ministry of Public Security on Wednesday set up a national DNA databank to track children who are the victims of kidnapping.

Early this month, the ministry launched its sixth nationwide campaign to deal with human trafficking.

About 3,000 kidnapping cases of children and women have been officially reported and investigated by Chinese authorities annually, but some experts estimate that 10,000 to 20,000 Chinese women or children have been kidnapped.

(Xinhua News Agency April 30, 2009)