An explosion has killed at least 20 soldiers in Pakistan’s restive northwest. Around 30 others were injured.<br /><br />The Pakistani Taliban says it was behind the attack as an army convoy was preparing to leave a military base near Bannu. <br /><br />The town stands at the gateway to North Waziristan, a lawless, tribal region on the Afghan border where many al Qaeda-linked militant groups are holed up.<br /><br />The Pakistani Taliban vowed to step up attacks on security<br />forces after electing a new hardline leader late last year.
