A Chicago family got the ultimate shock when they found out the brother that they had taken off life support was still alive.

Rosie Brooks received a surprise phone call with the news that her brother was near death at Mercy Hospital last month.

“She identified herself as Jennifer from Mercy Hospital,” Brooks told CBS Chicago. “She was a social worker. She was looking for relatives of Alfonso Bennett, and I told her that was my brother. And she said, ‘Well, he’s here in ICU.’”

When she showed up to the hospital with her sister, Brenda Bennett-Johnson, Brooks could not identify the man that police were calling her brother. The man had been badly beaten, especially in the face, and found naked and without identification weeks before.

“They kept saying CPD identified this person as our brother,” Bennett-Johnson said.

Neither of the sisters had seen their brother for years and could not identify him themselves.

But because he was in decline, the women signed off for the man to be taken off the ventilator and gave permission for doctors to perform a tracheotomy.

He died soon after, and the sister started funeral arrangements.

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But things took a shocking turn when they found out their brother was still alive. Alfonso Bennett suddenly walked into the home of another sibling soon after.

“You don’t identify a person through a mugshot versus fingerprints,” Bennett-Johnson said. “Fingerprints carries everything.”

“It’s sad that it happened like that. If it was our brother and we had to go through that, that would have been a different thing,” she added. “We made all kinds of decisions on someone that wasn’t our family.”

The police are now looking for the dead’s man family after having identified him through fingerprints.

A hospital spokesman maintains that Brooks identified the man as her brother.

“The family did identify this patient as their brother.”

Chicago police has launched an investigation.