A 22-year-old man is facing multiple murder charges after two women were found stabbed to death in separate attacks on Long Island, in a case that has stunned local residents and raised urgent questions about what led to the violence. Rony Yahir Alvarenga Rivera was arrested after allegedly carrying out a series of brutal assaults that began inside a shared home and ended hours later in a fast-food restaurant parking lot.

Police say the events unfolded over the course of a single night, beginning in Valley Stream, New York, and continuing into nearby Island Park. Authorities describe the attacks as deliberate and severe, with both victims suffering multiple stab wounds. Rivera has pleaded not guilty, and the investigation remains ongoing as detectives work to establish a clear motive.

According to Nassau County police, the first attack took place at around 9 p.m. on Thursday inside a residence in Valley Stream. Rivera is accused of killing a 32-year-old woman who lived at the home. While officials have not publicly confirmed the exact nature of their relationship, they stated that Rivera had been living with the victim.

Investigators believe the attack was sudden and violent. The woman was reportedly stabbed multiple times in the neck and torso, injuries that proved fatal. Emergency responders were called to the scene, but there was nothing they could do to save her.

What makes the case particularly alarming is what police say happened next. Rather than remaining at the scene, Rivera allegedly left the home and traveled several miles to a Wendy’s restaurant in Island Park, where he worked. Authorities believe he arrived there in the early hours of Friday morning and waited in the parking lot.

It was there, prosecutors say, that he carried out the second killing. A 42-year-old coworker was attacked while taking out the trash during her shift. She too suffered multiple stab wounds in what investigators have described as a frenzied assault.

The two killings, occurring within hours of each other, have led police to characterize the case as a deliberate sequence of violence rather than a random incident. Detectives are now working to determine what, if any, connection existed between the two victims beyond their link to Rivera.

The suspect’s arrest came shortly after the second attack, following what authorities describe as a chilling admission. According to Det. Lt. George Darienzo, Rivera approached police in Lynbrook and asked to speak with officers.

“When police arrived, he said he killed somebody that night,” Darienzo said. “A short conversation ensued, and an arrest was made. At that same time, information was received that this individual may be responsible for a second murder.”

Police confirmed that Rivera allegedly made a phone call after the Wendy’s attack in which he stated, “I’ve killed someone.” That statement, combined with the evidence collected at both crime scenes, led to his arrest on multiple charges.

Rivera, who is originally from El Salvador, entered the United States in 2016 at the age of 12, according to authorities. Officials have described his immigration status as undocumented. However, investigators have not indicated that this aspect is directly related to the motive behind the attacks.

At this stage, police have not released a clear explanation for why the killings occurred. Authorities have suggested that Rivera appeared to be in an angry state, but no specific trigger has been confirmed. The lack of an obvious motive has only deepened the concern felt within the community.

Residents in both Valley Stream and Island Park have expressed shock that such acts of violence could occur so close to home. For many, the idea that the suspect allegedly targeted people he knew—first a roommate, then a coworker—has made the case even more unsettling.

“For him to go out of his way to kill his roommate down the street and then go all the way to a Wendy’s that he worked at to kill his coworker, he must have had something against them really bad,” one local resident told reporters.

The identities of the victims have not yet been publicly released, pending notification of their families. What is known is that both women lost their lives in circumstances that investigators are describing as extremely violent and deeply tragic.

Law enforcement officials have emphasized that the investigation is still in its early stages. Detectives are continuing to gather evidence, interview witnesses, and examine Rivera’s background in an effort to understand what led to the attacks.

Rivera has since been arraigned and has pleaded not guilty to the charges against him. He is expected to remain in custody as the case moves forward through the court system. Prosecutors are likely to present evidence from both crime scenes, as well as statements allegedly made by the suspect, as they build their case.

The legal process will seek to establish not only whether Rivera committed the acts he is accused of, but also the circumstances surrounding them. Questions about his mental state, his relationships with the victims, and the sequence of events will all be central to the proceedings.

For now, the double killing has left a lasting impact on the communities involved. The events of that night have disrupted the sense of safety many residents once felt, replacing it with uncertainty and grief.

As investigators continue their work, authorities are urging anyone with information to come forward. Even small details, they say, could prove important in building a complete picture of what happened.

The case stands as a stark reminder of how quickly violence can unfold and how devastating its consequences can be. Two lives have been lost, families have been left grieving, and a community is struggling to make sense of a tragedy that occurred in the span of just a few hours.

As the judicial process begins, the focus will turn to the courtroom, where evidence will be examined and arguments presented. For the families of the victims, however, the search for justice is only part of a much larger process of coping with loss.

What remains is the memory of two women whose lives were cut short, and a case that now demands answers about how and why such violence took place.