Chen Shiqu, director of the Ministry of Public Security's anti-human trafficking office, said police have stopped child trafficking from increasing, but the practice is still prominent in some regions.

"We have zero tolerance when it comes to child trafficking and will make the utmost efforts to make sure that every trafficker is caught," Chen said on Friday.

In the raid carried out on Monday, more than 10,000 police officers, under the ministry's command, launched operations simultaneously, catching the suspects and rescuing the children in 15 provinces including Hebei, Shandong, Sichuan, Henan, Fujian and Yunnan, according to a statement released on Friday.

Two child trafficking gangs were smashed, Chen said, and all the rescued children were sent to welfare homes.

Shao Zhongyuan — listed as a top-level fugitive for allegedly being involved in a gang that trafficked more than 100 children — was arrested during the raid in Zaozhuang, a city in East China's Shandong province, the statement said.

In December, four suspects were caught trafficking four children in Luohe, Henan province, when police were inspecting a long-distance bus going from Shenzhen, in Guangdong province, to Shijiazhuang, the capital of Hebei province.

The suspects led the police to a major child trafficking gang, headed by Li Shichun and Hou Enzhuo.

In April, police in Xingtai, Hebei province, tracked down another child trafficking gang, headed by Yang Xuehua and Ji Xiaofang, who trafficked children using a private gynecological clinic in Pingxiang county. Local police said they had noticed that pregnant women from other places and children were often coming in and out of the clinic.

The clinic's owner, Guo Yanfang, confessed to the police on Tuesday that she began to help Yang and Ji's child-trafficking ring in 2008 and that she was mainly responsible for finding out the gender of unborn babies and seeking buyers, according to the Beijing News.

Yang and Ji, both from Southwest China's Sichuan province, brought pregnant women from Sichuan to Xingtai. The babies were sold locally or to neighboring provinces, the report said.

The two suspects were also involved with three other similar clinics in Xingtai.

The suspects confessed that the babies' genders and the mothers' appearance would result in different prices and they also introduced a bidding mechanism in order to earn more money, the report said.

Yang could get 6,000 to 8,000 yuan (940 to 1,300 U.S. dollars) for trafficking a child. Guo could get 2,000 to 5,000 yuan for successfully introducing a buyer, while a pregnant woman could receive 30,000 to 50,000 yuan, police were quoted as saying by the report.

The ministry listed the two trafficking gangs as special cases that had to be dealt with in February and May. With the efforts of local police, the ministry found Li Shichun and his gang were trafficking children from Yunnan to Hebei, Fujian and Henan via Guangdong, while Yang Xuehua's gang was trafficking children from Southwest China's Sichuan to places such as Hebei and Shandong.

As of Thursday, all major suspects, including the four gang leaders, had been caught, the ministry's statement said.

On Friday, Chen Shiqu said the ministry will also strengthen cooperation with non-governmental organizations to launch a crackdown on child trafficking.

Baobei Huijia, or Baby Back Home, a Jilin-based voluntary group in Northeast China that helps search for missing children and offers support to parents across China, is an organization that the ministry wants to works with.

Zhang Baoyan, founder of the non-governmental group, which has more than 20,000 volunteers nationwide, said they've provided more than 1,000 messages involving both missing children and parents' calls for help to the ministry since 2009.

"Our staff members communicate with police officers every day about missing children's clues and also provide the parents' DNA information to help missing children find their parents," she said.