Three people were killed in a mysterious explosion in a luxury apartment building in the Philippine capital, a government minister said Saturday, as officials lowered the death toll from the blast.
Interior Secretary Mar Roxas said authorities were still trying to assess what had triggered the blast but that initial investigations found no evidence of a bomb.
"We still have not seen any triggering device of any kind among the debris," Roxas told reporters hours after the explosion in a fifth floor unit in the high-end condominium, while bomb-sniffing dogs had found no sign of explosives.
"We are not ruling out anything," he told reporters just before touring the shattered apartment.
The explosion late Friday knocked out the wall of the condominium unit, sending a huge chunk of rubble hurtling to the street where it crushed a delivery van, killing the three men inside.
The government's National Disaster Risk Reduction and Management Council had earlier said that three other men had been found dead in the room where the blast occurred but later withdrew the statement saying it was inaccurate.
Hours later, debris from the building still littered the area, with some pieces of rubble hurled dozens of metres (yards) by the force of the blast.
The once-bustling area around the condominium remained cordoned off as police and fire investigators searched the building.
Roxas said they would treat the area as a crime scene to preserve evidence until they had determined the cause of the blast.
Roxas said the explosion injured five people including a US national who was hit by flying glass and the occupant of the unit, who suffered burns.
The condominium, located in an upper-class residential development called "the Fort" had been evacuated while it underwent an inspection, he added.
The explosion took place just a few metres away from a popular area of restaurants, bars and shops that attracts thousands of people at the weekend.
Philippine civilians have in the past been targeted in bomb attacks, often carried out by the Abu Sayyaf, a Muslim extremist group started in the 1990s with seed money from the Al-Qaeda network.
The 2004 Abu Sayyaf bombing of a ferry in Manila killed more than 100 people in the worst terrorist attack in the country's history.
However the group is largely concentrated in the southern Philippines rather than Manila.