Philippine marines who were searching for long-held hostages battled Al Qaeda-linked militants in a fierce clash that killed four marines and at least two insurgents in the country’s south, officials said. The fighting erupted in the mountainous hinterlands of Patikul town in Sulu province, where the Abu Sayyaf movement has survived in jungle encampments despite years of US-backed Philippine military offensives. Twenty-two marines were wounded in the daylong clash on Sunday that involved up to 200 Abu Sayyaf fighters and their allies, officials said.