According to The Daily Express, Muwaffaq Mustafa Mohammed al-Karmoush, also known by his code name Abu Salah, was killed in the bombings in the recent weeks.
US military spokesman Colonel Steve Warren confirmed the deaths from the Iraqi capital Baghdad.
Colonel Warren said Salah was "one of the most senior and experienced members" of the militant group's financial network.
The Pentagon also confirmed that a senior leader of IS was killed in Libya.
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