Chicago (CBS) — A deadly robbery in Park Manor Thursday morning took the life of a 64-year-old father who was on the phone with his son when he was targeted and tried fighting back.

Police were on the scene quickly, but both the victim and the attacker — each with a gun — died in the process.

The family of Mark Miller Sr. identified him as the landlord who was shot and killed. They say he was walking into the nearby building to let a plumber in for maintenance.

Mark Miller Sr. had a valid concealed carry license and returned fire, hitting 33-year-old Joseph Lewis, who also died. (Photo provided)

Family member Tony Lewis said Miller was talking on the phone with his son when the violence broke out.

“He went ‘hey dad, did you make it over there to the house?'” Lewis said. “My cousin hears boom boom boom boom boom boom. Mark Sr. says, ‘son, man I’ve been hit.'”

Police say Miller Sr. had a valid concealed carry license and returned fire, hitting 33-year-old Joseph Lewis.

Both eventually died after the gunfire.

Investigators say they found two firearms at the scene of the suspected armed robbery.

“That young man may have thought that my uncle was there to collect some rent money,” Lewis said. “What he keeps in his bag is the keys to other properties that he owns. Maybe he didn’t have any money, so maybe he thought my uncle had some money. It would be an easy robbery.”

Miller’s family says it’s not the first time he’s needed to defend himself whil on the job.

They are in the process of making funeral arrangements.