Chad Robertson, 25, died in a Chicago hospital a week after being shot in the back while fleeing from a pair of Amtrak police officers outside of Union Station. His death was ruled a homicide and a result of a gunshot wound to the back, according to The Chicago Sun-Times

Robertson was shot during a layover on a Megabus trip from Memphis to Minneapolis. Robertson and two companions were approached by a pair of Amtrak police officers who then followed them outside.

When the officers stopped them a second time, Robertson “feared for his life” and fled. That’s when one officer dropped to one knee, removed his weapon and fired at Robertson twice after claiming he saw a gun. Chicago police have reported that Robertson was unarmed.

Robertson’s death came a day after a federal lawsuit was filed on his behalf. A “wrongful death component” will now be added to the nine-count civil rights suit, according to the family’s attorney, Douglas Hopson.

The officer who fired the shots, LaRoyce Tankson, 31, has been charged with first-degree murder, according to DNAInfo.

“Amtrak is deeply saddened to learn of the passing of Chad Robertson,” said Amtrak spokesman Marc Magliari. “Amtrak is cooperating fully with the Chicago Police Department and State’s Attorney’s office as they conduct an independent investigation.”

The two officers involved in the shooting have reportedly been placed on restrictive desk duty.

During his last day in the hospital, Robertson was a quadriplegic because of the damage the bullet, which doctors couldn’t remove, did to his spine.

“When he found out about his condition from the doctors, he was heartbroken,” his sister, Nina Robertson, said at a press conference. “He just said, ‘The police ruined my life.’ ”

The Sun-Times attempted to obtain recordings of the incident, but Amtrak refused to release them due to the ongoing investigation.

“He was taken from us,” Nina Robertson said, “and we are confident that we will get justice. We are glad today that [Tankson] was charged. We know we will get justice, and that this is just the beginning.”