The Ministry of Public Security said police shot and killed four members of the eight-member terrorist gang Saturday at the scene of the attack, China's state-run Xinhua News Agency reported.
The knife-wielding attackers struck out at crowds at Kunming Railway Station, killing 29 people and injuring 143.
Chinese President Xi Jinping urged law enforcement officials to investigate and solve the matter quickly so the terrorists could be punished.
Reacting to the massacre, the Changshui International Airport in Kunming stepped up security checks Sunday, Xinhua said, saying travelers at the airport will be subject to more frequent and more intense body and luggage scrutiny.
The U.N. Security Council said in a statement Sunday the 15-nation body strongly condemned the attack.
A commentary published by Xinhua criticized the United States for allegedly downplaying the slaughter.
"The U.S. Embassy in China has downplayed the severity of the bloody carnage in southwestern Kunming City, calling it on its official Weibo account a 'horrible and totally meaningless act of violence,' short of calling the murderers 'terrorists,'" the commentary said
"How the U.S. government and some media described the terrorist attacks in China has revealed their persistent double standard in the global fight against terrorism," the commentary said. "Their leniency for the terrorists is sending signals of encouragement to potential attackers."