Police say a man is in custody for fatally stabbing his cousin at his Hauppauge workplace and then stabbing his cousin's girlfriend at her Brentwood home.

Wilson Melina is accused of stabbing his cousin to death early Thursday at Electrical Machine Parts on Oser Avenue, where they both worked.

Police say Melina left Hauppauge and went to his home in Brentwood, where he stabbed his cousin's girlfriend. The cousin's girlfriend is in critical, but stable condition.

Melina allegedly confessed to his girlfriend about the stabbing over the phone. His girlfriend then called police.

"Wilson Melina told her, 'Not only did I stab your sister, I also stabbed your sister's boyfriend,'" says Suffolk County Police Commissioner Rodney Harrison.

While police were on their way to the Brentwood crime scene, they found out about the stabbing in Hauppauge.

"As we're reporting, we also receive another call from the store owner here at this location who informs us that an individual here who has multiple stab wounds and has died from his injuries," says Harrison says.

Melina was found by police in Bay Shore and arrested without incident.

Police say he does not have a criminal history and are still trying to figure out the motive.

"He gave us a couple reasonings why he did it, but we don't believe they're the actual reason why he committed these heinous acts," Harrison says.

Police say they have not recovered a murder weapon yet.

Melina is charged with murder in the second degree and assault in the first degree.