The shooting of a Minneapolis man by Amtrak police in Chicago earlier this week was denounced Friday, while an attorney for the family said an investigation into the incident has moved swiftly.

The injured man, Chad Robertson, 25, who is black, remained at John H. Stroger Jr. Hospital, recovering from a gunshot wound to the left shoulder.

On Friday, his family said he is paralyzed and clinging to life. Nina Robertson, his sister, told the Associated Press that he has been in and out of consciousness and is unable to move or feel anything below his shoulders.

"He opened his eyes at the hospital, and the first thing he said to me was 'Why did they shoot me? I didn't do anything,'" said his sister. "When he found out about his condition from the doctors, he was heartbroken. He just said, 'The police ruined my life.'"

Robertson was taking a bus from Memphis to Minneapolis and was on a stopover at Union Station, Chicago's main transit hub, when the shooting occurred Wednesday evening.

The officer who shot Robertson, whose name has not been released, is also black, according to Douglas Hopson, a Chicago attorney who is working for Robertson's family.

Chad Robertson of Minneapolis, pictured with his girlfriend and two children, was shot and wounded by an Amtrak police officer in Chicago Wednesday.

Robertson's aunt, Pastor Theresa Love Williams of the Standing Love Christian Center in Robbinsdale, told reporters Friday that her nephew was shot "for no apparent reason" and was unarmed and running away when the officer fired.

"He posed absolutely no threat," she said.

Mel Reeves, a longtime Minneapolis civil rights activist who organized the news conference, said, "We demand the police be prosecuted."

On Thursday, Amtrak spokesman Marc Magliari confirmed in a statement that a police officer for the train agency was involved in a shooting, and that the Chicago Police Department and State's Attorney's office are investigating. The officers involved remained on administrative assignment in accordance with department policy as of Friday afternoon, Magliari said.

Authorities have so far released few details about the shooting, which occurred about 8:45 p.m. at an intersection just south of Union Station, according to news reports.

"This is just one of the more egregious examples of excessive force, of complete disregard of the life of a suspect, who happened to be black, but the officer was black as well," said Hopson. He said a grand jury would consider this week whether or not to charge the officer, who fired twice as Robertson fled an encounter with two transit officers, hitting him once.

"Running has become basically a death wish in this country," Hopson said, adding that investigators have been more transparent than in the past.

"The investigation was immediate. It was thorough. They shared information with me that just a few months ago wouldn't be released."

Nina Robertson said in a telephone interview with the Star Tribune on Thursday that her brother and two friends had ducked into the station to warm up during an hourlong layover on a Megabus trip back to Minneapolis from Memphis, where Chad Robertson and another man had attended a funeral.

According to Nina, the three friends were in a waiting area for Amtrak passengers when several transit officers approached them and asked them to leave. The trio started walking back toward the bus, but returned a few minutes later after realizing that they'd forgotten one of their bags, she said.

What happened next is in dispute.

The officers again confronted the pair, alleging that someone complained that Robertson's friend was smoking marijuana, and started to frisk the friend, relatives said.

"The officers followed them half a block away where everything went bad," said Hopson, the family's attorney.

Relatives said that Robertson, who had several run-ins with the police as a youth that escalated his fear of law enforcement, panicked and started running away from the officers when one of them opened fire.

"I'm so broken from this, because that mentality got him shot," Nina Robertson said. She said Thursday that a bullet remained lodged near his spinal cord.

Chicago police officials said in a statement that they recovered cash and drugs on Robertson, and that charges are pending.

Pastor Williams said that Robertson grew up on the North Side of Minneapolis and had gone to North High School.

"We need to stop the violence," she said.

The Associated Press contributed to this report.

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