both forms were made out to dolores delgado. dolores bought matched the caliber of gun that had killed karlyn. >> we saw that this gun was one of the ones on the list. >> of itself this purchase of a gun wasn't a smoking gun. but the detectives had to wonder why dolores would lie to them about owning a weapon. and there was something else. meyers soon learned that dolores had put a box of. 38-caliber ammunition up for sale on facebook. >> now, that's obviously you can't say it's the same bullets, but it matched all the characteristics. >> all this sleuthing took months. and while the detectives were working, dolores moved to san antonio, texas, into an apartment not far from maliek kearney. 150 miles west. karlyn's mom knew nothing about this new person of interest despite staying on the detectives. >> it's me again. i just don't want you to forget my daughter because she was very much loved. >> the investigation now encompassed a half dozen states. but maryland detectives and fbi agents were homing in on dolores delgado. >> wha