Jamal Ja'far Muhammad Ali Al Ibrahim, known by the kunya Abu Mahdi al-Muhandis was an Iraqi commander of the Popular Mobilization Forces (PMF). At the time of his death, he was deputy chief of the PMF and regarded as one of Iraq's most powerful men.

The Popular Mobilization Forces (PMF), also known as the People's Mobilization Committee (PMC) and the Popular Mobilization Units (PMU) is an Iraqi state-sponsored umbrella organization composed of approximately 67 different armed factions, with around 230,000 fighters that are mostly Shia Muslim groups, but also include Sunni Muslim, Christian, and Yazidi groups. The Popular Mobilization Units as a group was formed in 2014 and have fought in nearly every major battle against ISIL. Many of its main militias, in particular the Shias, trace their origins to the "Special Groups", Iranian-sponsored Shi'ite groups which previously fought an insurgency against the United States and the Coalition forces, as well as a sectarian conflict against Sunni Jihadist and Ba'athist insurgents. It has been called the new Iraqi Republican Guard after it was fully reorganized in early 2018 by its then–Commander in Chief Haider al-Abadi, Prime Minister of Iraq from 2014 to 2018, who issued "regulations to adapt the situation of the Popular Mobilization fighters".