The incident occurred around 7:30 a.m. at Jiatian International Mansion, which is in Xi'an, the capital of Shaanxi province, a city fire prevention bureau spokesman told Xinhua.
The blast led to broken windows 2 to 3 kilometers (1 to 2 miles) from the site, with many cars damaged and a sign over a bus stop blown away closer to the site.
The spokesman characterized the explosion as an "accident," according to the state-run news organization.
Authorities sealed off the area, guarding against possibly more explosions and casualties, according to Xinhua reporters on the scene. Source