The government said that the destruction of the stockpile, gathered from seizures since 2009, demonstrates its commitment to fighting the illegal ivory trade. It also eliminates any opportunity for corrupt officials to resell the ivory, as was the case in 2006 when the largest single shipment of 3.7 tones vanished from the inventory, according to an international network that tracks the illegal trade.
"Ivory is known to have disappeared from a number of government-held stockpiles worldwide, so it is vital that proper protocols are established," said Colman O Criodain from the World Wide Fund for Nature.
The U.S. Agency for International Development and the anti-wildlife-trafficking Freeland Foundation said they were helping the Philippines analyze DNA of tusks at the Center for Conservation Biology of the University of Washington so that law enforcement agencies will know the origin and transit points of the smuggled ivory. It will also help to dismantle criminal syndicates responsible for poaching in Africa.
"This not only sends a message to wildlife traffickers that the Philippine government is taking firm action against the illegal ivory trade, but also takes a stand against corruption by burning their ivory stockpile so it cannot be stolen then sold into the black market," said Steven Galster, director of Bangkok-based Freeland Foundation.
Ivory can fetch up to $2,000 per kilogram ($910 per pound) on the black market and more than $50,000 for an entire tusk.
The Elephant Trade Information System, which tracks the illegal trade on behalf of the 1989 Convention on International Trade in Endangered Species, says that the Philippines is among nine countries and territories identified as being most heavily implicated in the illegal trade. The others are Kenya, Tanzania, South Africa, Malaysia, Vietnam, Hong Kong, China and Thailand.
The Philippines is a transit point but also is known for its carving industry producing religious sculptures and artifacts.
Last year, National Geographic magazine featured an ivory collection allegedly belonging to a Roman Catholic priest, Monsignor Cristobal Garcia, who was suspended in 2012 by the Vatican because of a sex abuse case. The Philippines' National Bureau of Investigation has said it would question Garcia over the origin of the ivory icons.
Officer Sixto Comia said Friday he had not received any reports on the result of the investigation.
Associated Press writer Oliver Teves contributed to this report.