Investigators examine the area of an explosion in Taguig City, the Philippines on May 31, 2013. Three people died in the explosion, while four people were injured according to reports. (Xinhua/Rouelle Umali)

Passers-by and rescuers look at an exploded condominium unit in Taguig City, the Philippines, May 31, 2013. Three people died in the explosion, while four people were injured according to reports. (Xinhua/Rouelle Umali)

Firemen look at vehicles damaged in an explosion in Taguig City, the Philippines on May 31, 2013. Three people died in the explosion, while four people were injured according to reports. (Xinhua/Rouelle Umali)

Workers gather shattered glass after an explosion in Taguig City, the Philippines on May 31, 2013. Three people died in the explosion, while four people were injured according to reports. (Xinhua/Rouelle Umali)