Police say 40-year-old Erick McCormick is the man who was caught on surveillance video in Brownsville following the shooting death of his ex-girlfriend, 46-year-old Sellis Gonzalez.
The woman's two children, one of whom is fathered by McCormick, found her body last week inside their Chauncey Street apartment.
Community activists will ask for help in front of the church where Gonzalez's funeral will be held.
Authorities say McCormick showed up at the home around 8 p.m. Wednesday and gave the girls money to buy fried chicken at a restaurant around the corner.
When they returned, NYPD Commissioner Ray Kelly said, they found the door ajar and their mother in a pool of blood, shot six times. Gonzalez was reportedly shot three times in the head and three times in the chest.
She was rushed to Brookdale Hospital, where she was pronounced dead on arrival.
McCormick is described as a black male, 5-foot-8 and weighing 225 pounds.
Anyone with information in regards to whereabouts of Eric McCormick is asked to call the NYPD's Crime Stoppers Hotline at 800-577-TIPS.