Two kidnappers were executed Thursday for abducting and murdering two children in Shenzhen, a boom city in south China's Guangdong Province, a local court said.

The Intermediate People's Court of Shenzhen said the death penalties for the two abduction-for-ransom convicts, Kong Jinlin and Shu Luwen, were approved by the Supreme People's Court.

Kong, a 36-year-old from Meizhou City in Guangdong, kidnapped a 11-year-old schoolboy in Futian District on November 17, 2009 and demanded 1 million yuan (about 150,000 U.S. dollars) in ransom from the boy's father. The boy was suffocated to death the next morning when Kong tried to silence him.

Shu, 23 and a native of the central Hunan Province, kidnapped a five-year-old girl in October 2005 and demanded 20,000 yuan from her father. He later suffocated the girl to death.

The booming town of Shenzhen launched a campaign at the end of last year to crack down on kidnapping and other serious crimes following a string of abductions of school children.

Two other kidnappers were executed in March for their actions that led to the deaths of children.