Police suspicions shifted to Warmus when she began to relentlessly stalk Solomon, following him and Ballor to Puerto Rico and calling Ballor's family in an effort to end the relationship. When investigators gained information that Warmus had obtained a .25 caliber Beretta pistol with a silencer shortly before the murder, Detective Richard Constantino checked calls made from Warmus's home phone on January 15. He discovered one made at 3:02 p.m. to Ray's Sport Shop in North Plainfield, New Jersey. Store records indicated the only female to purchase .25-caliber ammunition that day was Liisa Kattai from Long Island. When questioned, Kattai denied ever being in the shop or buying ammunition. Further investigation determined that Kattai's driver's license had been lost or stolen while she was employed at a summer job, where one of her co-workers was Warmus. Police now had enough evidence to make an arrest.