ST. LOUIS • When a man pulled a gun and announced a robbery during a drug deal early Saturday, the robbery victim said, “You’ll have to shoot me,” according to police.

The gunman did, opening fire and killing Joseph M. Lee, 19, in the 3700 block of Pennsylvania Avenue, according to court documents.

A Kirkwood man, James Allen Columbus, was charged Tuesday with murder, attempted robbery and armed criminal action in the shooting. Key to the case was a confidential informant who set up the drug deal, according to court documents.

Lee’s body was found by the basement door at the back of his home on Pennsylvania in the Gravois Park neighborhood about 11 a.m. Sunday, police said.

But the informer told police he was there when Columbus shot Lee hours earlier. The informer told police he set up a meeting between Columbus and Lee because Columbus wanted to buy marijuana.