Chinese authorities are investigating a fresh explosion in Guangxi province, a day after a series of blasts killed seven people.

The explosion took place at a house at around 08:00 local time (00:00 GMT) in Liucheng county, said state media.

The cause was not clear, and no casualties have been reported.

Seventeen separate explosions hit Liucheng on Wednesday, which police believe were caused by bombs placed in the mail.

The local postal service has halted all deliveries until Saturday.

State media said besides the seven dead, another two people remained missing and 51 people were injured.

A 33-year-old man, identified only by the surname Wei, has been arrested.