For mail carrier Stephen Spina, a day off on Sept. 17, 2007, was supposed to mean a lazy morning bumming around the apartment, grabbing lunch with his girlfriend and an evening date with his one true love, his daughter Skylar in their town of Mamaroneck, New York.

When Spina wasn't delivering the people their mail, he was umpiring their kids at the local ball field. And yet, someone in the quaint little town wanted him dead. And police still don't know who.

It was a Monday. For Spina, it was what might be more like someone else's Saturday, a day off. As far as Spina's girlfriend, Tamara Acevedo, knew, there was nothing to indicate the day would be anything but normal.

At around 9:30 a.m., a neighbor witnessed Spina walking out to his car. That was the last anyone saw of Mamaroneck's beloved mail carrier, until Acevedo showed up for lunch. And when she gets the superintendent to unlock the door, she walks into a horror show. Spina was found inside, stabbed to death.

For such a violent scene, police found no sign of forced entry and nothing missing, clues that he may have known his killer. Not surprising, considering where he lived.

With the clock ticking, police search the area for clues, and begin the hunt for suspects. One of cops' biggest tips came from the victim himself, not long before his murder. Apparently, Spina had been arguing with a local contractor around the same time as his tires were slashed.

While detectives continue looking closely at that suspect, they've also been digging into some of Spina's past relationships. After all, the evidence did suggest a personal connection. But still, police have been unable to conclusively implicate, or rule out, anyone, including Spina's girlfriend, Tamara Acevedo.

While police believe they may be closing in on their killer, they are still asking for the public's help. There's a $40,000 reward for information leading to the killer's conviction.

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