Philippine troops renewed their attacks on al-Qaida-linked militants and their supporters, shelling a camp a week after the guerillas beheaded seven Filipino hostages, officials said Thursday. TV images showed a row of army artillery guns firing toward a mountain hide-out of the al-Qaida-linked Abu Sayyaf rebels on southern Jolo island, where officials said a local Muslim separatist commander, blamed for recent clashes with government troops, had joined forces with the Abu Sayyaf. The artillery attacks began Wednesday. The Abu Sayyaf militant group - the target of a monthslong US-backed offensive that has killed its two top leaders - last week decapitated seven Christian construction workers and had civilians deliver their remains to army troops on Jolo. "At present, the military operations on Jolo are continuing," said military commander Maj. Gen. Ruben Rafael.