Suspect in deadly Long Island stabbings lived with 1 victim, worked with 1 of them, police say

Police identified the suspect in the deadly stabbing of two women on Long Island, saying he lived with one of them and worked with the other.

Nassau County Police said the investigation started early Friday morning outside a Wendy's in Island Park. That's where Ana Maria del Aguila-Cordova, 42, was stabbed to death. She's a mother of two from Long Beach. 

How the investigation unfolded

Early Friday morning, police were called to the scene at the Wendy's for a report of a person with a knife, Det. Lt. George Darienzo said.   

"When the officers responded, they observed a young lady laying on the ground, with blood. The officers administered first aid and pronounced that 42-year-old female deceased," Darienzo said. 

Darienzo said surveillance videos and photos were recovered while they were processing the Wendy's crime scene. A suspect who matched a person seen in the surveillance videos and photos was spotted near a 7-Eleven in Lynbrook. 

"Officers responded and that individual said he had killed somebody that night," Darienzo said. "A short conversation ensued, and an arrest was made." 

While they were taking the suspect into custody, police became aware he may be responsible for a second murder at a home on West Mineola Avenue in Valley Stream, Darienzo said. Officers made a wellness check at that home, and found Eddy Raquel Hernandez Castillo, 32, dead. Police said Castillo was likely killed at 9 p.m. on April 30, before the other woman was discovered murdered at Wendy's. 

"Both females were killed by multiple stab wounds to the neck and torso," Darienzo said.

Police said they were not aware of any relationship between the two victims.

What we know about the suspect

Police identified the suspect as Rony Alvarenga-Rivera, 22. He's facing murder charges. 

Darienzo said the suspect and Hernandez Castillo lived in the same household, where they rented separate bedrooms and shared a living room, kitchen and bathroom.

Alvarengo-Rivera and del Aguila-Cordova were coworkers at Wendy's, Darienzo said. 

According to police, the motive for both stabbings was anger.

"Our hearts go out to the two individuals who were murdered," Blakeman said. "But I want to stress that this didn't have to happen." 

Alvarenga-Rivera is originally from El Salvador. Blakeman, who is running for governor, said the suspect came to the United States in 2016 as an unaccompanied minor.

"This is a policy that has resulted today in two women being killed," Blakeman said. "They could've gone on to have very productive and happy lives. But they're no longer with us because of failed policies in the past."

CBS News New York reached out to the Department of Homeland Security about the suspect's citizenship status, but has not heard back.

Alvarenga-Rivera is due back in court Tuesday.