Chicago brothers run down and shoot a man 18 times, police say. Authorities called the shooting an 'execution.'

Two brothers in Chicago chased down and killed a young man with a barrage of bullets on April 5, as police say it was like an execution.

Semaj Dixon, 28, and a second gunman were accused of firing a combined 18 shots at the victim, hitting him 11 times as he tucked into the fetal position, authorities said.

The second gunman is Dixon’s brother, but they did not release his name because his whereabouts are unknown at this time, police said.

According to authorities, Dixon’s ankle monitor’s GPS placed him near the scene of the shooting, then he left and returned to the area before police arrived.

Authorities have not said if a weapon was recovered.

The Chicago Tribune reported Dixon’s attorney, Nicholas Giordano, challenged the ankle monitor findings during a hearing, as he claimed Dixon lives near the scene of the shooting.

Giordano stated Dixon contacted officials before asking for permission to leave the area because of death threats and added that a third Dixon brother was killed in the same area.

According to video footage, the victim, Eugene Broach Jr., 21, can be seen fleeing through an alley before stumbling and falling around 3:45 p.m.

That is when both gunmen stood over Broach and fired numerous shots at close range, authorities said.

It was just six hours later that Dixon was arrested, as police say they found him wearing the same pants as in the surveillance video.

Dixon’s pants were tested and a spot tested positive for gunshot residue where he allegedly touched them after the shooting, police said.

There was no known relationship between Dixon and Broach, according to authorities.

Dixon was charged with first-degree murder charges, as well as escaping while on electronic monitoring and armed habitual criminal, authorities said.

He is being held without bail pending trial and the judge barred him from contacting witnesses.