No casualties were reported in the attack, which inflicted light damage to the building.
During the investigation process, police seized four pro-governmentdemonstrators at a house near the NACC together with some arms,including a grenade launcher and grenades.
Theattacks took place just before caretaker Prime Minister YingluckShinawatra is to go before the NACC on March 31 to defend herselfagainst accusations that the government has neglected corruptionwarnings during the implementation of the rice subsidy programme,causing big economic losses.
If the NACCofficially indicts Yingluck, the case will be transferred to the Senatewhich may conduct a vote on whether to impeach her.
Pro-government supporters have been camping in front of the NACC forseveral days with a plan to hold a mass rally on April 5.-VNA