Pictures that call for the "death penalty for all child traffickers and immediate execution " have gone viral on Wechat, a popular social networking site.

According to China's criminal law, whoever abducts and traffics a child shall be sentenced to at least five years in prison. Under eight aggravating circumstances, including trafficking more than three persons, sexual abuse, and use of violent means, the trafficker shall be sentenced to more than 10 years, up to life imprisonment. If the circumstances are especially serious, he/she shall be sentenced to death and also to confiscation of property.

In fact, China has kept a heavy punishment for children trafficking. Official figures show that courts across the country handled over 7,700 such cases between 2010 and 2014. Some 13,000 people were punished and over 7,000 of them were given sentences greater than five years in prison.

And the death sentence, which netizens have called for, has never been ruled out.

Lan Shushan, who abducted 34 children aged from 3 to 10 and sold them for over 500,000 yuan (about $81,334) from 1998 to 2008, was sentenced to death earlier this year.

In another case, Ma Shouqing and his accomplices abducted and sold 37 children from 2006 to 2008, with one female infant dying during transportation. He got the same punishment as Lan and was executed.

How do other countries fight against child abduction?