Shanell Crute and her boyfriend were walking toward East 163rd Street in the Bronx to buy marijuana that night. With two blocks to go, they stopped when a group of five guys called out to her. The men had been drinking and smoking.

Ms. Crute’s nickname was Sweetz because she was quite friendly, but that night, Sept. 30, 2010, she gave as good as she got for the last minutes of her 26-year-long life.

“She says, ‘I might know these guys,’ ” said Lt. James Ruane of the 44th Precinct detective squad. “She gets into a bit of an argument with them when she figures out she doesn’t know these guys. Somebody said, ‘Get the Waka Flocka.’ ”

Two men broke off, crossed East 161st Street, entered the lobby of an apartment building, approached the bank of 207 mailboxes and opened one.