The Afghan Taliban claim responsibility for the attack . But Sunday 's attack was a troubling reminder of the region 's volatility even as officials consider pulling out troops . Officials had just announced plans for ` ` phased withdrawal '' of troops from some areas . The blast is a troubling example of the Taliban 's volatility .
The Afghan Taliban claim responsibility for the attack . Officials had just announced plans for ` ` phased withdrawal '' of troops from some areas . The blast is a troubling example of the Taliban 's volatility .