Seven people were killed and 51 injured in 18 blasts on September 30 and October 1. The multiple explosions targeted, a shopping mall, a prison, a government building, a supermarket and a hospital in the remote Liuzhou city in the southern region of Guangxi.
The lone suspect, 33-year-old Wei Yinyong, was killed in one of the explosions.
His body has been identified through DNA tests.
The police statement said Wei was in dispute with villagers over a stone quarry he had a stake in.
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Wei's brother and father told the Hong Kong based South China Morning Post that Wei was frustrated when protesting villagers forced the closure of the quarry and the local authorities failed to negotiate a solution.
"I don't accept the accusations. There's not enough evidence," Wei's brother has been quoted as saying by the paper.
Wei had been the manager of the Zhihao Stone Quarry since it opened in 2003.
Angered by the frequent explosions at the quarry, more than 100 residents from the village of Zhaijiaotun, less than one km from the site, marched to the quarry on October 28, 2013, and smashed the machines, forcing an immediate shutdown.
Wei became withdrawn in the second half of 2014 after repeated requests to local government departments to resolve the dispute ended without success, his brother said, adding he knew there was no way the quarry could reopen but he just wanted a solution from the government.
Wei's frustration was evident on a social media page which he created.
"When it comes to a day when I become crazy, please remember I have been fooled like an idiot when I was pure and innocent," one of the posts on microblog by Wei said.
Villagers confirmed Luo's account of the smashed equipment.
"His quarry was smashed for a reason," one resident said.
"Kids were scared of the sound of the explosions and windows were damaged by its shock waves," he said.