Three M-79 grenades were shot and landed in the 1st Antiaircraft Artillery Regiment base, not far from the PDRC protest site in Chaeng Wattana.
The first grenade landed near the protest site.
The other two landed inside the 1st Antiaircraft Artillery Regiment base, one falling in front of the parking building, 200 metres from the PDRC stage. Another fell behind the 1st Company building, causing slight damage.
No media access was allowed.
Phra Buddha Issara, PDRC leader at the Chaeng Wattana rally site, said that he heard three explosions at about 10.30pm.
He believed that the assailants may have intended to shoot the grenades at the place he stayed but if so they missed the target .