Rony Yahir Alvarenga Rivera, 22, was arraigned on Saturday, May 2, 2026, on charges of first-degree murder and two counts of second-degree murder following a pair of fatal stabbings in Nassau County. Rivera, an undocumented immigrant from El Salvador, allegedly killed his roommate and a co-worker in separate incidents that occurred between Thursday night and early Friday morning. During his appearance at First District Court in Hempstead, he pleaded not guilty and was ordered held without bail.
The violence began on Thursday evening at a residence on West Mineola Avenue in Valley Stream. Prosecutors stated that Rivera allegedly attacked his 32-year-old roommate “without warning,” stabbing her more than 50 times in her upstairs bedroom. Police believe this initial killing occurred hours before the second attack, though they only discovered the victim during a welfare check at approximately 3:13 a.m. Friday after Rivera was already in custody.
The second fatal incident occurred shortly after midnight at a Wendy’s on Austin Boulevard in Island Park, where Rivera was employed. He allegedly targeted a 42-year-old co-worker, identified by her family as Ana Maria de Aguilla Cordova, as she was taking out the trash. Police responding to a 911 call at 12:27 a.m. found Cordova outside the restaurant with fatal stab wounds. Family members described her as a hardworking mother who had “no enemies”.
Following the second stabbing, Rivera reportedly entered a 7-Eleven in Lynbrook and asked a clerk to call the police because he was “in distress”. Arresting officers took him into custody without incident at approximately 7:00 a.m. Friday. While a specific motive has not been released, investigators confirmed that Rivera knew both victims as they lived in the same shared household where bedrooms were rented individually.