Several police vehicles set off from a police station in Tianlin, a county of Baise city in the Guangxi Zhuang autonomous region, late on Tuesday night.

More than 150 police officers from the city were divided into three groups and dispatched to Tianlin, Longlin and Xilin counties to capture human traffickers.

A police officer plays with a child rescued in an anti-human-trafficking campaign in Linyi, Shandong province, on Wednesday. [Zhang Zheng / for China Daily]

As of Thursday, 16 suspects had been arrested.

In fact, Guangxi was just one of 14 "battlefields" in the Ministry of Public Security's crackdown against human trafficking action this week. More than 7,000 police officers participated in the campaign in 14 provinces, including Henan, Shandong, Shanxi, Yunnan and Guizhou.

As a result, 310 suspects were arrested and 77 kidnapped children were rescued.

The children were mostly kidnapped in Yunnan province in Southwest China and Guangxi in South China and sold to other regions, such as Shandong province in East China and Shanxi province in North China, according to the ministry.

After finding clues in October, police conducted investigations in different provinces. To ensure the rescued children's safety, some provincial public security bureaus used their offices as shelters and assigned policewomen to look after them, the ministry said.

Huang Dewei, chief of the crackdown in Tianlin county, said the biggest difficulty faced in Guangxi was the local geography.

"The three counties are mountainous, meaning it was easier for suspects to evade us," Huang said.

Long Yuegang led a group of 10 colleagues to Ding'an village, about 90 km from Tianlin county, to arrest a female suspect whose home was in the mountains.

"We first called two policemen who already had the suspect under surveillance," said Long, adding that the mountain road was difficult to drive in the dark.

"We were also afraid of dogs barking as we went toward the village," he said.

But conducting the operation at night was convenient, since most of them would probably be asleep.

"She was ready for bed when we entered her home. We immediately caught her," he said.

By about 3 am, the arrests were over, and the police turned their attention to questioning the suspects.

A woman surnamed Yang, 37, one of the arrested suspects in Longlin county, Guangxi, confessed to the police that she had trafficked six infants for money since 2010.

Police said Yang bought infants younger than one month from other villages in the county and Guizhou province and sold them to people in Central China.

Each infant was sold for 3,000 ($475) to 4,000 yuan, police said, and she could get about 800 yuan per child.

According to police, she said all the infants were baby girls and she did it only for money.

Liu Zhiqiang, chief captain for solving criminal cases in Guangxi, said the traffickers always used different mobile phone numbers to make it more difficult for the police to find them.

"Some suspects discarded cell phone cards after finishing one transaction and some used several phone numbers to confuse the police," Liu said.

In 2011, police across the country cracked 5,360 cases involving the abduction of women and 5,320 cases involving children. Meanwhile, 3,195 gangs were destroyed, and 8,660 children and 15,458 women were rescued, according to statistics from the ministry.

Jiang Yue, a professor at Xiamen University's law school, said: "The main reason for human trafficking is the economic gap and some residents in poor areas even think such trafficking is a way to earn money".

Besides, cutting off demand market and enhancing awareness of this issue are also necessary, or the problem will not be solved, she added.

Xu Wei in Beijing contributed to this story.

You may contact the writer at caoyin@chinadaily.com.cn