Police say the coffee bar explosion on December 24 and two bus explosions on July 21 in southwest China's Kunming City were carried out by the same man.

Du Min, vice mayor and head of the public security bureau of Kunming, capital of Yunnan Province, said on Saturday that a man named Li Yan was seriously injured last Wednesday in an explosion at Salvador's Coffee House, a Western restaurant in Kunming, about 10:40am.

Li was rushed to a nearby hospital but he died two hours later.

The accident caused no other casualties or injuries and there was little property damage. After analyzing explosive traces and Li's DNA, police confirmed that Li was the man involved.

Du said Li was walking out of the bathroom when an ammonia bomb in his backpack unexpectedly exploded.

Further investigation by police showed Li, from Xuanwei City in Yunnan Province, had been sentenced to jail for nine years on November 15, 2001 for robbery, intentional injury and vandalism. He worked as an electrician at the jail.

He was released early for good conduct on May 30, 2006.

Police searched Li's apartment and found ammonia explosives, detonators, bullets and a home-made gun. They said Li acquired these materials while working on a road project in July 2007.

Traces of explosives from the coffee bar matched those from the two Kunming bus explosions in July.

The Institute of Forensic Science of the Ministry of Public Security and the Forensic Science Center of the Public Security Department of Yunnan Province confirmed that biological evidence from the coffee bar and bus explosions matched Li's DNA and material found in his apartment.

Two people died and 14 were injured on July 21 as explosions occurred on two buses in Kunming.

(Xinhua News Agency December 29, 2008)