MANILA, Philippines -- (UPDATE 2) The death toll in Thursday’s explosion at a pyrotechnics factory in Trece Martires City, Cavite has risen to eight, with eight persons still missing, the Department of Labor and Employment (DoLE) said Friday.

Ricardo Martinez, regional labor director for the Cavite-Laguna-Batangas-Rizal-Quezon region, said their office also recorded 74 injuries from the explosion at the Star Maker fireworks factory.

The owner of the fireworks factory in Cavite province is facing criminal and civil charges, a police official said Friday.

The blast at the Star Maker Fireworks in Trece Martires City killed six people and wounded 70 others.

In Malacañang, Executive Secretary Eduardo Ermita said President Gloria Macapagal-Arroyo has ordered police to conduct a thorough investigation on the incident and to make sure those found liable are punished.

"The President directed the PNP [Philippine National Police] to conduct a thorough investigation, look into the background of Star Maker, and look into violations of law,” Ermita said.

Among the questions that need to be answered, he said, is: “Why is the factory in a populated area?"

In a phone interview, Chief Superintendent Perfecto Palad, Calabarzon (Cavite, Laguna, Batangas, Rizal, and Quezon) said the collateral damage of the explosion alone amounted to around P3 million, including those that were destroyed at the provincial capitol and hospital.

Palad said the have yet to determine the cost of the damages to other private properties.

“Wasak yung buong perimeter eh [The whole perimeter was destroyed],” he added.

Palad said police were looking at the incident as an accident as initial investigation revealed that prior to the explosion, one of the employees was testing a firecracker.

He said that the area had been secured, although firefighters were on standby as several types of pyrotechnics and some 100 kilograms of black powder were found among the debris.

“Baka sumabog may mga usok-usok kaya naka-standby ang fire truck [These might explode, there’s still smoke that is why a fire truck is on standby],” Palad said.

Palad said that official police count of casualties was six, four of which have been claimed by their families. Six others are missing, as police continue to scour the area to look for more bodies.

Palad said several of the victims were charred beyond recognition.

Of the injured, 65 had been discharged from the hospital while two remained in critical condition, Palad said.

The DoLE’s Martirez said authorities are looking at three possible causes of the explosion: explosive materials stored in a van under the heat of the sun; new products being tested at the time of the explosion; and chemicals stored inside the building.

Dulce Gust, executive director of the DoLE's Occupational Safety and Hazardous Center, reiterated that apart from meeting the standards of safety, the culture of safety must also be developed in workplaces, especially fireworks factories.