A senior leader of the self-proclaimed Islamic State of Iraq and Sham (ISIS) was killed by coalition airstrikes, said the U.S. military on Thursday.

Tariq bin Tahar al-'Awni al-Harzi, who helped fundraise, secure arms and transport militants for the group was killed by the June 16 airstrike, according to the Pentagon. Pentagon said that he was the brother of another fighter linked to the 2012 attack on a U.S. diplomatic compound in Benghazi, Libya.

"His death will impact ISIL's ability to integrate foreign terrorist fighters into the Syrian and Iraqi fight as well as to move people and equipment across the border between Syria and Iraq," said Captain Jeff Davis, a Pentagon spokesman, using a different acronym for the ISIS group.

The Pentagon had previously declared that Harzi's brother was killed in a U.S. airstrike on June 15 on Mosul, Iraq.

The U.S. previously offered $20 million for four senior ISIS leaders including al-Harzi.