MIAMI (CBSMiami) – Detectives have linked a pair of teenagers to two unsolved murder case in Northwest Miami-Dade.

They did not have to go far to find the teenagers because they were already in jail.

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The two teens are being linked to a series of violent crimes that happened between March and May.

Mugshots for 16-year-old Antione Lynch (left) and 18-year-old Jaquavius Matthews (right). (Source: Miami-Dade Corrections)

Over the crime spree, one person was killed over $50 and fake gold chain.  Another was killed over absolutely nothing.

Now police have connected the dots that could put these two young men away for life.

In April, Shelsy Medina was shot and killed outside her mobile home in Honey Hill.

Her heartbroken family made a plea for witnesses to step forward.

“If they would have known her, they would have never done this to her. They could have taken anything but my baby’s life,” Medina’s mother Sotrosa said through tears.

The victim’s father Waldo Medina tried to make sense of it as well.

“Absolutely meant the world to us. She was my princess, and I still don’t understand,” Waldo said.

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Detectives shared surveillance video from the neighborhood but they didn’t know who was on it.

A few weeks later, a deadly robbery took place in Opa-locka. This time it was Omar Alvarez robbed at gunpoint.  Alvarez died over $50 dollars and his fake gold chain.

Glenda Medina spoke to CBS4 in tears.

“He was heartless, he didn’t care. He left two little girls without a father,” she said of the shooter.

Surveillance video held some clues. When the thieves tried to sell Alvarez’s belongings, police were able to solve the case.

Arrested is Antione Lynch, who is just 16 years old, and Jaquavius Matthews who is 18 years old. Police have also linked another armed robbery to them.

Yalier Rodriguez, who lives just a few homes over from Shelsy Medina’s home, says his spouse moved out.  She was unable to deal with what had happened.

“We were worried because we have kids,” he said.

Many neighbors were relived police finally caught those responsible. Still, they are heartbroken over what happened.

“The poor lady died for nothing. They didn’t take anything,” Rodriguez said.

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Both teenagers are charged with first degree murder and being held with no bond.