WSVN — Gary Karp can't sleep, can't work, can't believe what has happened.

Gary Karp: "This is something that I would never ever in a million years thought that it would ever happen to me. I come from a Jewish family, these things don't happen."

What happened five years ago? His 17-year-old daughter Marissa was murdered. When she was buried, part of Gary went with her.

Gary Karp: "Marissa was a child. She didn't deserve this."

In fact, the main reason Gary lives is to search for his daughter's killers, to find out why they did what they did.

Gary Karp: "Probably the most difficult question that I ask myself on a minute by minute basis is that did she know what was going to happen to her? What were the last few minutes of her life like? Who did she ask for?"

In August 2002, Marissa was shot in the chest and killed, probably at her Hallandale apartment. Her body was then stuffed in a trash bag and dumped in the Everglades right over the Collier County line.

John Turchin: "This is a jurisdictional nightmare. She was probably murdered, they believe, in one county, in Broward County, and then she is dumped in another county, in Collier County."

Patrick Fraser: "Collier County detectives are now in charge of the investigation. They didn't want to talk to us, telling us there was nothing new to add, so we turned to America's Most Wanted and John Turchin who also investigated this case and still waits for the killer or killers to be caught."

John Turchin: "Unfortunately, Marissa died a horrible death. But what really bothers me in this case, the thing that gets stuck in my crawl is the way they disposed of her body. I just think of my kids, and the fact that somebody can take a life so easily and then dump it like its trash. It hits home, it just wakes you up real quickly."

And Marissa was a normal kid, until her mother died when she was 11. She was devastated, and her pain turned to anger.

Gary Karp: "She started having some issues as far as anger management. I think she was very angry. She was hard to manage, and she started doing her own thing."

At one point, she moved in with her grandmother, then beat her up and was arrested. When she was released she became a runaway.

Gary Karp: "Chronic runaway, she ran away several times and had been brought back. You know, she was with the wrong crowd."

And someone in that crowd probably killed her.

According to this search warrant we obtained, a neighbor heard a gunshot the night she was murdered, near the Hallandale apartment she shared with her boyfriend.

A bullet hole was found in her refrigerator. A cell phone reportedly used by her boyfriend was recorded pinging numerous times from Hallandale out into the Everglades where her body was found. Police suspect people know what happened but they are not coming forward.

John Turchin: "For them, from their point of view, they don't want to be looked at as a rat and talk, and, the other side of it, some of them don't want to take the chance that if they do rat, maybe they are going to end up in the same place Marissa did."

There is DNA evidence. There are leads for detectives. But just not enough without someone stepping forward.

John Turchin: "I think it's fair to say that the detectives that are handling this case from Collier County are very confident of the group of people that she was with, that may be involved in this, it's proving it that is the issue."

And proving it is all that Gary asks for, all that he lives for.

Gary Karp: "People know what happened to Marissa. They need to really come up."

John Turchin: "Gary doesn't give up, and he is not going to do so until this case is solved, until he has an answer."

Gary Karp: "They need to step up and do the right thing. They don't want to do it for me, that's fine, but do it for Marissa."

Do it for a little girl who was normal, until she saw her mother die, saw her life fall apart, turned away from her family and turned to the wrong people.

Gary Karp: "Marissa deserves better than this. She'll be known as the girl they found in a canal in a garbage bag, and that's not the way I want her to be remembered."

Not remembered this way. Remembered this way: a young girl with a future who passed away, leaving behind another family still Out for Justice. If you have any information about Marissa's killer or killers, you can call the Collier County or Broward Sheriff's Department.

FOR MORE INFORMATION:

Collier County:1800-780-TIPS

Broward Sheriffs Department: 954-493-TIPS

Out for Justice MIAMI-DADE: 305-598-HELPBROWARD: 954-796-HELP

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