TAMPA, Fla. (WFLA) — The mother of Nilexia Alexander spoke out for the first time since an arrest was made in her daughter’s murder.

The Tampa Police Department held a press conference with Ashley Alexander Friday, the day after 44-year-old Ronny Walker was arrested in connection with the teen’s death.

“I want to thank God for this day,” Ashley Alexander said. “I prayed that this day would come, they would get him off the streets.”

Police said Nilexia, a runaway, was found dead in a vacant field on Floribraska Avenue on May 6. The 14-year-old died of a gunshot wound.

The Tampa Police Department worked with the State Attorney’s Office, the Florida Department of Law Enforcement and the U.S. Marshals Service to identify and apprehend Walker.

Police said cellphone records show Alexander was in Walker’s vehicle around the time she was killed. Her DNA was also found inside his vehicle, according to police.

Walker was arrested Thursday and charged with premeditated first-degree murder with a firearm.

State Attorney Andrew Warren said the investigation was still active and ongoing, and specific information was being withheld.

Police would not say Walker and the teen knew each other.

Warren asked that anyone with additional information on Nilexia’s murder come forward.

Warren said Walker was charged with second-degree murder in 2009 in the death of Elaine Caldwell, but was convicted of a lesser charge of manslaughter in 2010. That conviction was overturned on appeal, and he was sentenced to eight year in prison. He violated his probation in 2017 by drinking alcohol, and got another four years in prison, Warren said.

“If he would’ve been in prison, he would have never had a chance to kill this baby. He killed a baby, 14-years-old,” Caldwell’s daughter, Veronica Denson said. “He is an animal. He should have never been on the street. If they let him out again, what is he going to do next time.”

“The reality is that most people that go through the criminal justice system don’t go to prison for life,” Warren said. “Had he been convicted back in 2010 of murder two, then maybe it would have been different. If there weren’t appellate issues in the case, maybe it wouldn’t have been different.”

“Prosecution is complicated,” Warren added. “Back in 2010, I have confidence that the state attorney’s office did everything they could to convict him of the charge against him. He was ultimately convicted of a lesser charge and this sentence reflected that.”

“I thank everyone who was able to bring this person to justice—I thank you,” Ashley Alexander said. “It won’t bring my baby girl back, but it will give me some peace that he is off the streets and a little bit of closure.”

“This is just the beginning,” she added.