This is horrible, but hostage-taking is an established feature of Islamic law: "As for the captives, the amir [ruler] has the choice of taking the most beneficial action of four possibilities: the first to put them to death by cutting their necks; the second, to enslave them and apply the laws of slavery regarding their sale and manumission; the third, to ransom them in exchange for goods or prisoners; and fourth, to show favor to them and pardon them. Allah, may he be exalted, says, 'When you encounter those [infidels] who deny [the Truth=Islam] then strike [their] necks' (Qur'an sura 47, verse 4)" -- Al-Mawardi, al-Ahkam as-Sultaniyyah (The Laws of Islamic Governance).
"Officials: Taliban Take 30 Pakistani Children Hostage In Afghanistan," from Radio Free Europe/Radio Liberty, September 2 (thanks to all who sent this in):
Pakistani officials say Taliban militants in Afghanistan have taken hostage around 30 Pakistani children who crossed the border by mistake. They said the incident took place on September 1 after the group of boys, aged between 12 and 18, visited an area of Pakistan's Bajaur tribal region for celebrations marking the Muslim Eid holiday when they crossed into the Afghan province of Kunnar and were abducted....