By CBS3 Staff

PHILADELPHIA (CBS) — A 25-year-old suspect confessed to the murder of 2-year-old Nikolette Rivera, sources tell Eyewitness News. Philadelphia police took a second suspect into custody Wednesday in connection to the young girl’s shooting death in Kensington.

Police say the second suspect has not been formally charged and his identity has not been released. He was taken into custody on unrelated charges, according to police.

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Nikolette was killed Sunday afternoon when police say a gunman fired an AK-47 assault rifle into her family’s Kensington home on the 3300 block of Water Street.

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On Tuesday night, Freddie Perez was arrested by Philadelphia police in Chester. He has been charged with murder and nine counts of attempted murder on Wednesday morning.

Nikolette was in her mother’s arms when she was struck in the back of the head and killed.

Police say the suspects intended to kill Nikolette’s father.

“He was clearly targeting the house. The father was not at home at the time but that’s clearly where the beef was,” Acting Philadelphia Police Commissioner Christine Coulter said.

Nikolette’s 24-year-old mother was shot in the right side of her head and once in the back.

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A 33-year-old man doing renovation work inside the home was also shot.

Both are expected to survive.

Police sources say Perez was driving a distinctive looking car while an accomplice on the passenger side started firing a rifle into the home.

A car linked to Perez was captured by a security camera a few blocks away from the deadly shooting scene over on Clearfield Street. That’s where two men inside the car were seen shooting up a parked car and leaving behind important ballistic evidence.

No one was hurt there, but it happened less than 10 minutes before Rivera was killed.

“From that video, we were able to get a very good description of the car,” Coulter said.

Authorities also say while security video showing the suspects’ car led them to Perez’s home, tips from the public helped them identify him.

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CBS3’s Matt Petrillo contributed to this report.