One person has been killed and eight injured in a series of small explosions outside the provincial headquarters of the ruling Communist Party in the northern Chinese city of Taiyuan.
Official statements posted online gave no information about the presumed target or perpetrators and an official with the party propaganda office, Zhang Lei, said he had no additional information.
One of the injured was listed as serious and two vehicles were damaged.
Photos from the blast showed the street in front of the headquarters building closed off and fire trucks, ambulances and police vehicles parked in the area.
One showed a man lying on the ground, but there were no obvious signs of an explosion.
A street cleaner interviewed on state television said the explosives were planted in flower beds in two separate locations and that eight blasts were heard in all.
Footage showed the blast scene littered with nails and steel balls of various sizes, apparently packed into the bombs to cause maximum damage and injury.
Blood stains were visible on the street and on a damaged vehicle.