CHICAGO (CBS) — A shooting on the platform at the Howard Street Red Line in the Rogers Park neighborhood has left one person dead.

The reported shooting happened around 12:40 p.m., and police say a 20-year-old man was shot in the chest and neck. He died at St. Francis Hospital in Evanston.

Police say the shooter walked up to the victim and opened fire.  The offender fled out of the CTA station and ran northbound on Paulina Street, police said.

Police told CBS 2’s Vince Gerasole the shooting happened on the platform and in the station.

There was no prior conflict between the shooter and the victim outside the station, police said at the scene.

The victim was known to police, officers said.

Detectives said late Tuesday afternoon that they were are questioning people of interest, and a gun was recovered at the scene.

CTA said there are significant delays on the Red, Purple and Yellow lines.

Police investigate a reported shooting near the Howard Street Red Line. (CBS)

CHECK: CTA Updates

Immediately following the shooting, trains were held at Howard “due to a police investigation,” the CTA said. By 2:30 p.m., Red Line trains were again running to and from Howard, but with major delays.

As an alternative to the Red Line, the CTA also encouraging people to use #22, #36, #151, #147 or any other buses.

Yellow Line trains are currently suspended, but customers are encouraged to use #97 Skokie Bus.

Purple Line trains operating between Linden and South Boulevard. There are shuttle buses between Howard and South Avenue.