Col. Nonato Peralta, anti-terror Task Force Zamboanga commander, said the 10 rounds of 60mm mortars were concealed in a sack and left near a commercial ferry bound for Jolo, Sulu and Bongao, Tawi-Tawi.
"There is very less possibility that this cache of ammunition is for the political groups because we have ongoing offensive in Sulu and the Abu Sayyaf is said to have run out of logistics and ammunition," he said.
Peralta said soldiers had been tightly watching the wharf after receiving information from civilians on a plan to ship the ammunition a few days ago.
Troops were inspecting passengers and baggage when they noticed the suspicious cargo near the boat and ready to be loaded at about 7 p.m. Wednesday, he said.
Peralta said the military’s explosive and ordnance disposal unit is investigating the source of the ammunition, as there is no indication that it came from the armory of the Armed Forces.
"There are also indicators that the ammunition could have come from abroad, and it is very unlikely it came from our logistics because we have already increased security as far as pilferage of our logistics is concerned," he said.
The military and police continue to impose tight security in the different ports to prevent lawless elements from slipping explosive materials aboard ships.