MANILA - AC Energy said Monday initial investigations showed that the Iloilo oil spill from its power barge was likely due to an explosion in its fuel oil storage that raptured the tank. Cleanup efforts will likely last for 15 days.

The firm's power barge 102 in Barrio Obrero, Iloilo City discharged fuel at around 3 p.m. on July 3, AC Energy said in a disclosure to the stock exchange.

The leakage was contained at 10 p.m. the same day, it said.

"The root cause is yet to be determined, but initial findings reveal that the discharge is attributable to ignition of fuel oil in storage which ruptured the barge’s fuel tank," the Ayala-led unit said.

The company has tapped Harbor Star, a maritime service provider, to finish the cleanup for both the waters and the coastline, AC Energy said. Cleanup is estimated to last up to 15 days, it said.

Some 120 households have been relocated while the cleanup is ongoing. AC Energy said it would continue to coordinate with officials in the containment efforts.

It will also tap third-party experts to determine the root cause of the explosion, it added.

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