
The attack was made at 2:10 am against a group of some 20 protesters who were standing and talking outside a gate of the Government House.
Anupong Samerphak, a PAD guard, 22, was hit by bomb shrapnel at his body and neck. Ramathibodi Hospital doctors put him on respiratory system.
Earlier, there were confusing reports that he succumbed to brain injuries.
But Doctor Than Suphatphan, the director of the hospital said at 1:20 pm that Anupong was still living on the respiratory system. He said doctors would not pull the plug but would let him to live as long as possible.
He was initially declared brain-dead by the hospital but later pronounced dead.
Eyewitnesses said two teenagers parked their motorcycle near the back gate of the Metropolitan Police head office and used a grenade launcher to launch a grenade at the protesters. The two fled the scene on Phitsanulok Road.
The injured protesters were standing near the Fifth Gate of the Government House Complex opposite from the Education Ministry.
The explosion caused a small hole in the ground and damaged two pick-up trucks, a sedan car and a motorcycle near the scene.
Maj Gen Anan Srihiran, commander of the Metropolitan Police Division 1, rushed to the scene with bomb disposal officers to carry out an investigation.
Pongchai Saetang, 42, a taxi driver, told police that he was waiting at the intersection for passengers when he saw a red light in the air, which was followed by a loud noise shortly.
He said the explosion occurred at the spot where about 20 people were talking.
The taxi driver said he saw two young men fleeing on their motorcycle on Phitsanulok heading to the Wang Daeng intersection.
The two men were about 200 metres away from the explosion spot when they ran to their motorcycle and fled, the taxi driver said.
The seven other injured were identified as Wirat Piangsajja, 54, Somchai Wongsonthi, 44, Pongchanok Kanchana-amorndej, 31, Samrerng Buachan, 26, Prakrong Hachai, 38, Narong Nakiam, 64 and Ekkapol Sahawat, 33.
All of them were rushed to the Ramathibodi Hospital by the PAD guards.
It was the second bomb attack after the tacit ceasefire during the royal cremation period.
Early Thursday, a grenade was launched at protesters inside the Government House complex, killing one and injuring more than 20 others.
The Thursday bomb prompted the PAD to declare war and plan a mass rally outside Parliament Sunday to try to speed up the downfall of the government.
The Manager Online reported that all leading members of the People's Alliance for Democracy will hold an urgent meeting at the Manger Group head office following the latest bomb attack.
After three hours of meeting, the PAD leaders held a press conference at 1 pm to announce that the mass rally would be held Sunday morning.
Chamlong Srimuang said the PAD learnt that the government would move up the charter amendments on the agenda when the House and Senate hold a joint sitting Sunday.
Chamlong said the bomb appeared to be fired from a corner near the Metropolitan Police head office. The attack showed that police would no carry out their duty to provide security for the demonstrators, he said.