Madison, Tenn. (WKRN) – He may be 72 years old, but you better not mess with Robert James Johnson.

“I’m a good shooter,” he told News 2.

Two robbery suspects learned that the hard way.

“They didn’t know who they were messing with,” Johnson said. “They messed with the wrong person that day.”

Police are piecing together a crime that took place on Wednesday afternoon, when Johnson agreed to help a woman who lives on the streets. They believe that same woman set him up to be robbed in order to pay off her drug debt.

Molena Holt, 26, asked Johnson to drive her to Springfield. But first, she needed him to take her to the Madison Manor Apartments to pick up some clothes.

When they arrived, she got out of the car and went around a building. Two men approached Johnson, saying he couldn’t park there.

That’s when they attacked.

“The other one grabbed me and said give me the money, give me the money, give me the money and the other one hit me, the other one had the gun,” Johnson recalls.

It was a setup.

“I was getting the gun out at the same time while he was asking for the money, when he was asking for the money, talking – POW!  I shot that bastard,” Johnson said.

Suspect Randall Caradine, 46, was hit in the chest area. He later died at Vanderbilt University Medical Center a short time later.

And Johnson told News 2 he didn’t just shoot; he shot to kill.

“So you just fired one time?” reporter Larry Flowers asked. He replied, “Yes sir. That’s all I needed to kill him.”

The other suspect got away with $1,000.

“Well I’m sorry I didn’t get the other one,” he said. “If I would have got out the car, I would have.”

The 72-year-old was the victim of a similar robbery nearly two years ago on Trinity Lane in Nashville.

“I was robbed before and I didn’t have nothing then, and I said I never be robbed again,” Johnson said.

Holt was arrested for facilitating a robbery all to pay off a $30 drug debt.

“I don’t mind helping people if I see somebody in need, if I can help them I will help them, but I’ll never do that again,” he said.

Police say Holt has previous convictions for drugs and prostitution. She remains in jail on a $100,000 bond.

The other robbery suspect is still on the run. Neither a description nor identity was released.