US military says airstrike kills ISIS leader in Syria

The United States has confirmed that the leader of the Islamic State in Syria was killed in an airstrike. 

Maher al-Agal was "responsible for aggressively pursuing the development of ISIS networks outside of Iraq and Syria," the U.S. military said. 

The strike hit northwestern Syria along the Turkish border. 

"Extensive planning went into this operation to ensure its successful execution. An initial review indicates there were no civilian casualties," said military sources. 

The military said a close associate of al-Agal was also seriously injured in the strike. 

This is the second high-level ISIS official killed this year. Abu Ibrahim al-Hashimi al-Qurayshi blew himself up during a U.S. raid in February.