Iraq's pro-Iranian militia named a successor to Abu Mahdi Al Muhandis, the former deputy head of the Hashed Al Shaabi military network.
Al Muhandis was killed last month when a US drone strike targeted a convoy also carrying Iranian Quds Force commander Qassem Suleimani at Baghdad airport.
The Hashed, also know as the Popular Mobilisation Forces, are a pro-Iranian, mostly Shiite militia grouping, nominally integrated into the Iraqi state.
The PMF named Abu Fadak al-Mohammedawi as the replacement for Al Muhandis, according to media reports. Abu Fadak - which is not his real name - is a senior official in Kataib Hezbollah, which was founded by Al Muhandis.
Kataib Hezbollah has been targeted by the US over the killing of an American contractor in a rocket strike on a military base in Iraq in December. That attack triggered the escalation that resulted in the killing of Al Muhandis and Suleimani.
An Iranian opposition group has previously claimed that an individual known as "Abu Fadak" has commanded Kataib Hezbollah forces in Syria, operating under Iran's direction.
Last month, Iraqi militia chiefs met in Iran to resolve a power struggle and differences on how to counter Washington after the death of Suleimani, who oversaw Iranian activities in Iraq.