The Pakistan Taliban said the attack was revenge against the Army for its crackdown in a tribal area. More than 130 children died in Tuesday's attack by gunmen on a school in Peshawar.
Economist Ilham Tohti received a life sentence in September for 'splittism' and 'inciting hatred.' Many in the academic and diplomatic community say he is a rare prominent voice of moderation.
Human Rights Watch says more than 7,000 civilians have died since 2009 at the hands of the extremist group. Nigeria recently announced a cease-fire that it said would allow for the release of more than 200 schoolgirls abducted in April.
The Nigerian government claimed earlier this week that it had reached a cease-fire deal with the Islamist group. But the reported kidnapping of between 20 and 70 more schoolgirls, on top of the more than 200 it already holds, is souring hopes for peace.