ZAMBOANGA, Philippines (CWNews.com) - Philippine soldiers on Monday searched a mountainous region in the south of the country for 27 Catholic hostages after they overran a Muslim rebel camp and did not find them there.

    The Abu Sayyaf rebel group has been holding the hostages, most of them children, for more than a month as they demanded the release of terrorists jailed in the US and the Philippines. After they beheaded two of their captives -- two male teachers -- two weeks ago, the army launched a major offensive against the rebels' mountain stronghold.

    "At present, we are scouring the area inch-by-inch but there is no more exchange of fire," Colonel Hajma Hailil, an army spokesman, told Reuters. "They have found three tunnels ... that's the problem, we don't know where the hostages are," he said, adding troops were being very careful because "there may still be landmines there."

    Hailil said the soldiers had not yet searched the main tunnel at the base, high up on the mountain.

    Meanwhile, the same Muslim rebel group has separately kidnapped 21 people from the nearby Malaysian tourist island of Jolo. The group includes 10 foreign tourists, including three Germans, two Frenchmen, two South Africans, two Finns, one Lebanese, and a Filipina. Hostage negotiators report that many of the captives are ill and in need of medical attention.