A building partly collapses during the explosion in Liucheng, South China's Guangxi Zhuang autonomous region.[Photo from CCTV's Sina Weibo]

Seven people were killed and two were missing on Wednesday after 17 suspected package bombs exploded in southern China's Guangxi Zhuang autonomous region, Xinhua News Agency reported, with blasts reported in more than a dozen locations, including government offices.

More than 50 people were injured by the explosions. The blasts apparently were triggered by devices placed inside express delivery packages, Xinhua said of the explosions, which occurred on the eve of China's National Day holiday.

The Ministry of Public Security sent criminal investigators to the scene and said that it was treating the series of explosions as a criminal act, and not terrorism, according to Xinhua.

Xinhua also quoted local police as saying that they are looking for a 33-year-old suspect from Dapu township surnamed Wei.

Five victims died at the scene, and one died at a hospital, according to Xinhua.

The explosions occurred in at least 13 locations in rural Liucheng, including a business trade mall, a prison, a government building in Dapu township, a supermarket, a bus station and a hospital, according to the local newspaper Nanguo Morning News and sources from the Liucheng county public security bureau.

Local government officials were quoted as saying that the series of explosions occurred between 3:15 pm and 5:30 pm.

State broadcaster CCTV quoted a local police chief as saying that the blasts were caused by several different explosive devices.

Pictures online showed a half-collapsed building. Witnesses also saw damaged vehicles on the road, Xinhua said.

The injured, some of them in critical condition, were being treated at Liucheng People's Hospital.

The local government launched emergency measures, and officials and rescue teams rushed to the affected areas.

The local administration of work safety issued a warning to the public to avoid opening such parcels that they might have received recently.

While the local government said the initial investigation indicates this is a criminal case, Dai Peng, director of the Criminal Investigation College at the People's Public Security University of China, said it might be too early to make such a conclusion.

The blasts might have exposed "loopholes of management of the express delivery industry", said Dai, who also suggested that the blasts might point to the need for real-name registration of both package senders and receivers.

Zhang Yan contributed to this story.

Contact the writer at hena@chinadaily.com.cn