IS 'minister of information' killed in coalition airstrike
Wa'il Adil Hasan Salman al-Fayad, also known as "Dr. Wa'il," was targetted in a precision strike on September 7 near Raqqa, the IS group's de facto capital in Syria.
He was considered by the Pentagon as one of the militant group's most senior leaders.
"Wa'il oversaw ISIL's production of terrorist propaganda videos showing torture and executions," Pentagon press secretary Peter Cook said in a statement, using an alternative acronym for IS.
Wa'il was a prominent member of the IS senior leadership group, the Shura Council, Cook added.
The Pentagon declined to comment on whether it was a US aircraft that conducted the strike.
"The removal of ISIL's senior leaders degrades its ability to retain territory, and its ability to plan, finance, and direct attacks inside and outside of the region," Cook said.
"We will continue to work with our coalition partners to build momentum" in the campaign to deal the IS group "a lasting defeat," Cook added.
Earlier this week the Pentagon announced that an airstrike last month killed the militant group's chief propagandist –and a close associate of Wa'il - Abu Mohammad al-Adnani.
Adnani, who served as the voice of IS over the past few years, was one of 43 original founders of the terrorist group with a $5m [£3.8m] bounty on his head.
Of the original 43 Islamic State founders, 41 have been killed so far according Iraqi terrorism expert Hisham Alhashimi.
The deaths of senior IS leaders serves a blow to the group, which has been on the retreat in Syria and Iraq.