WSVN — On the day we interviewed Tatiana Paul, it was her mother's birthday.

Tatiana Paul: "And the whole week, I've been thinking about it like it's a sign. Maybe it's a sign that she's sending me. Maybe she wants him to get caught."

Tatiana Paul, a teenager who had to endure something no person could bear to see.

Detective Tracy Lystad, North Miami Beach Police: "I couldn't imagine to lose your mother to something so brutal like that, and to not only hear about it, but to actually see it and to watch your mother basically die in your arms."

Tatiana's mother Coty was watching TV with a friend when her boyfriend Abraham Mpaka rang the doorbell. Coty came to the door.

Detective Tracy Lystad: "She just heard a brief scream from the victim. She looked over and saw him pulling the knife from her. He casually didn't say anything. He just took the knife with him and he just walked away."

A few seconds later, Tatiana was at her mother's side dialing 911 while trying to save her life.

Operator: "He stabbed her?"

Tatiana Paul: "Yes. He stabbed her."

Operator: "Tatiana, is she breathing?"

Tatiana Paul: "Yes. She's breathing."

Tatiana Paul: "She was trying to say something, but I couldn't, it wasn't clear enough for me to figure out what she was saying."

Tatiana's mother was dying in her arms. The knife had split her heart open.

Detective Tracy Lystad: "You can hear her on the 911 tape, which is even more devastating, you know, talking to her mother while she's taking her last breaths. I couldn't imagine having to deal with something like that at 14 years old. It breaks your heart."

Mpaka walked away. Detectives suspect he was afraid Coty was going to break up with him, so he went to a Wal-Mart a few hours earlier, where surveillance cameras captured him buying the knife.

Detective Cora Mann, North Miami Beach Police: "And then at the end, you see him put a knife, like a large kitchen knife, and he passed it through the register, and you see him engaged in conversation with the cashier."

He is accused of killing Coty, and ripped a mother away from a young girl and boy.

Tatiana Paul: "I miss being around her and not being able to talk to her about some of the things I would want to talk to her about."

Today, Detectives Lystad and Mann are trying to close in on Mpaka, while becoming very close to an incredibly strong 16-year-old.

Detective Cora Mann: "I've always told Tati, 'I didn't know your mom while she was alive, but your mom must have been a remarkable woman, because she helped raise a remarkable young lady.'"

Patrick Fraser: "What happened to Abraham Mpaka? He was from South Africa, spoke Creole and visited Haiti a few times. But there is no record of him ever leaving the country, leading detectives to wonder if he boarded a cargo ship and fled to Haiti."

Detective Tracy Lystad: "So he could very well be in Haiti, but he could also be in the community still. He fits very well in the community."

Fits in very well, because Abraham Mpaka is a con man, lying and luring people in.

Detective Tracy Lystad: "He claims he has a doctorate from the University of Paris, and from speaking with different people, he claims a lot of things. I believe that he's a very good con man, and unfortunately, Coty was conned by him, and unfortunately, it cost her her life."

Tatiana says he took her mother's life, and she fears Mpaka will come back to take her life.

Detective Tracy Lystad: "She always tell us, Detective Mann and I, that she can't sleep sometimes, 'cause she feels that he's going to come after her or her brother, and it's heartbreaking."

Heartbreaking, but then Tatiana inspires them by telling them her mother will find a way to take care of her.

Tatiana Paul: "And I do know that I have a protector and she's up there, and there's also another one, God. He's up there, and he's watching over my brother and I."

The detectives also watch over her and would love to give her one thing.

Detective Tracy Lystad: "I want to give her that phone call. Detective Mann and I want to go to the house and say, 'You know, we caught him. He's never going to do this to anybody again.'"

Abraham Mpaka is a con man: charming, convincing, cruel and an accused killer who police believe will murder again. He may be in South Florida. He may be in Haiti. If you have any clues, no matter how small, please call Miami-Dade Crime Stoppers. And a brave teenager also has another request, if you can spare the time.

Tatiana Paul: "Please keep my family and I and my brother in your prayers."

Patrick Fraser: "And if the right person makes a call, another prayer will be answered: a killer will be caught. And if you have lost a loved one, if you are still out for justice, give us a call."

Miami-Dade Crime Stoppers: 305-471-TIPS (8477)Out For Justice: 305-598-HELP (4357) in Miami-Dade or 954-796-HELP (4357) in Broward

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