Some religious authority should have issued a Fatwa condemning the act.

The Taliban draw authority from the following verse (9.29)

"Fight those who believe not in Allah nor the Last Day, nor hold that forbidden which hath been forbidden by Allah and His Messenger, nor acknowledge the religion of Truth, (even if they are) of the People of the Book, until they pay the Jizya with willing submission, and feel themselves subdued." -

see link

http://www.usc.edu/schools/college/crcc/engagement/resources/texts/muslim/quran/009.qmt.html#009.029

"When you meet your enemies who are polytheists, invite them to three courses of action. If they respond to any one of these, you also accept it and withold yourself from doing them any harm. Invite them to (accept) Islam; if they respond to you, accept it from them and desist from fighting against them. [...] If they refuse to accept Islam, demand from them the Jizya. If they agree to pay, accept it from them and hold off your hands. If they refuse to pay the tax, seek Allah's help and fight them."


Which is what essentially the Taliban told them - pay tax, or convert or fight.

“Dismantle terror infrastructure” S. M. Krishna tells Pak.
We must congratulate the literally new line he has taken regarding Pakistan and terrorism. Since Narasimha Rao days, it has been “Pakistan must dismantle its infrastructure of terrorism”.

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