Police are investigating a fatal shooting inside this Hyde Park apartment. (CBS)

Police are investigating a fatal shooting inside this Hyde Park apartment. (CBS)

UPDATED: 4/30/2013 10:55 a.m.

CHICAGO (CBS) — Police are looking for a gunman after a shooting in Hyde Park overnight killed one man and injured another.

It happened inside an apartment building in the 5200 block of South Harper, CBS 2’s Susanna Song reports.

Police said around 12:15 a.m. a man approached two men who were standing in the hallway and fired shots.

Henry Atkins, 39, was shot in the chest and died at the scene, according to the Cook County Medical Examiner’s office.

Luis Galvan, 22, was shot in the hand and was treated at the hospital and released.

Galvan told CBS 2 that he opened his apartment door for his friend, who stopped by to borrow some movies, but he wasn’t alone.

The gunman was also there and opened fire.

“The look on his face, he looked mentally unstable,” said Galvan. “I’m not sure if he was looking for drugs. I don’t know what pissed him off that day.”

After the gunman killed Atkins, Galvan thought he and his pregnant girlfriend were next.

“I was waiting for the rest of the shots to come. I saw my life flash before my eyes.”

However, the gunman then fled before police arrived.

Investigators are trying to get more details from the surviving victim, but there have been no arrests.

Police also do not know a motive behind the shooting.

Galvan said he doesn’t know either.

“I don’t know why he did it,” he said. “You’re in Hyde Park. You aren’t going to get away with nothing like that.”

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