A former security guard from the company Blackwater was found guilty on Wednesday of first-degree murder for the shooting of unarmed civilians in the Iraqi capital Baghdad in 2007. 35-year old Nicholas Slatten was among the responsible, alongside three other Blackwater guards, for the massacre in 2007, an incident that drew worldwide condemnation.

Slatten had previously been convicted in 2014, but a federal appeals court vacated this initial conviction arguing that he should have been tried separately from the other Blackwater mercenaries involved in the massacre at Baghdad's Nisur Square on Sept. 16, 2007. Slatten was convicted by a federal jury in Washington on Wednesday after five days of deliberation.

According to prosecutors, Slatten - from Tennessee (U.S.), started intentionally firing which killed at least unarmed 14 civilians and left at least 18 wounded, beginning with the death of the driver of a white Kia, Ahmed Haithem Ahmed Al Rubia'y, 19, the Washington Post reported.

This shooting has been known for its brutality and sparked the debate on the role of private security contractors, like Blackwater, who work for the U.S. government in several areas and regions. Slatten and his fellow guards were traveling in a heavily armed, four-truck Blackwater Worldwide convoy and had been trying to clear a path for U.S. diplomats after a nearby car bomb.

In the attack, Slatten and his fellow guards opened machinegun and grenade launcher fire on a crowd that included women and children. Prosecutor Fernando Campoamor-Sanchez told jurors Slatten took aim at Al Rubia'y through a scope and fired his sniper rifle twice because "he thought he could get away with it" and would "never have to answer to people like you," according to the report.

In the initial 2014 murder conviction, Slatten had received a life sentence, and the other three Blackwater mercenaries had received 30-year terms. However, they were overturned because, according to the federal appeals court, the three guards should have been tried separately. Blackwater, which was founded by former Navy SEAL Erik Prince, the brother of Education Secretary Betsy DeVos, was later sold and now operates as Virginia-based Academi.