Hafiz Saeed, the leader of the so-called Islamic State’s “Khurasan province,” was the highest ranking of three leaders killed this week in Afghanistan.
Several defectors from the Taliban pledged allegiance to the Islamic State in a video released over the weekend, and reports suggest they are a growing threat in Afghanistan.
The CIA restarted its covert drone war on Pakistan's North Waziristan on Wednesday in response to the Taliban attack on Karachi airport.
The Pakistani Taliban have claimed responsibility for an attack that killed at least 28 people at Karachi airport late on Sunday.
Deadly bombings at a market and train station come as a temporary ceasefire with the Pakistani Taliban is set to expire on Thursday.