Thailand ? A grenade attack on anti-government protesters occupying the Thai prime minister’s office killed one person and wounded at least 23 early today, an army official and protesters said.

The protesters have occupied the Government House compound since August and refuse to leave until Prime Minister Somchai Wongsawat resigns or is overthrown. The protest movement has been the focus of several small bomb and grenade attacks, but Thursday’s was the first deadly assault at the compound.

The explosion occurred shortly after 3 a.m. while a band performed onstage on the front lawn outside the prime minister’s office, said Amorn Amornratamanon, one of the protest leaders. The grenade landed on a giant tent near the stage that was sheltering dozens of people, he said.

Army Gen. Prathomphong Kesornsuk, who was at the scene, said the device was an M-79 grenade that was fired by a grenade launcher from a nearby building.