There has been another explosion in a region of southern China, hit by 17 blasts on Wednesday that left seven people dead.
This time it happened in a six-storey building in a residential district.
No-one is reported injured in Thursday’s explosion and it is not known if the blast is connected to the earlier series of parcel bombs in Liucheng county of Guangxi province.
Guangxi sits on the border with Vietnam and has several ethnic minorities, but is generally peaceful.
Dozens of people were injured on Wednesday when bombs were sent to places ranging from hospitals and shopping malls to prisons and government offices.
Two potential victims are still unaccounted for in what is said to be being treated not as a terrorist attack but as a ‘criminal’ act.
There are conflicting reports about whether a 33-year-old suspect identified by the police has now been arrested.
Disaffected or mentally unstable Chinese people have set off explosions in public places in the past.
Explosives are relatively easy to come by, as they are widely used in China’s large mining industry.
It is not known what may have motivated the blasts over the last two days but such “sudden incidents”, as Chinese authorities refer to them, are sometimes seen as linked to a widening gap between rich and poor and anger at corruption or environmental problems.