MANILA, Philippines, Oct 15, SPA -- Philippine troops on Sunday defused a bomb discovered just three hours before it was timed to explode near a market in the southern Mindanao region, the scene of recent terrorist attacks, police said. A guard found the bomb _ a rocket-propelled grenade and an M203 rifle grenade attached to an alarm clock and batteries_ in a backpack near the gate of the Agora market in Pagadian city in Zamboanga del Sur province, said regional police Chief Superintendent Jaime Caringal said. Investigators are looking for witnesses to determine who planted the bomb, which was found after dawn in theprovincial capital about 780 kilometers (485 miles)southeast of Manila, Caringal said. Troops and policemen later set up checkpoints andintensified patrols in Pagadian. «We're very closely guarding the piers, airports and allplaces where terrorist activities can happen,» Caringaltold DZBB radio.--SPA www.spa.gov.sa/396306