Tampa, Florida -- Larry Donell Brown is just 16 years old, but unlike most teenagers his age he is already considered a violent felon, racking up a criminal history that started at the tender age of 10.
Brown is now accused of a very adult crime: shooting and killing 38-year-old CIS security officer Michael Valentin on Thanksgiving eve.
Valentin was working at the Grand Oaks apartments in Tampa when he was gunned down. He was an armed security officer, but did not have time to pull his own weapon.
Valentin was a husband and a father to two young children.
"The bottom line is it's disheartening to see a 16-year-old senselessly destroy a family, take the life of an innocent, hardworking man," said Laura McElroy, with Tampa Police.
Police say they first identified Brown on Monday after he was linked to a gun theft that occurred in Hillsborough County the day of the deadly shooting.
"By Tuesday night, they learnt Larry Brown stole that weapon and he was charged with that offense on Tuesday night just a very short time after he committed he final violent act," explained McElroy.
Police say Brown robbed a USF student at gunpoint at an ATM. Surveillance video shows Brown with a bandana over his face, standing behind the young man.
It's the same crime police say he committed on Friday, two days after it's believed he shot and killed Valentin.
Surveillance video from that ATM robbery also shows Brown with a bandana covering his face.
It's very similar to a bandana worn by the man seen on another surveillance video riding his bike through the Grand Oaks apartments moments before the shooting Wednesday night.
The bike, left at the scene near Valentin's body has become a critical piece of evidence.
FDLE rushed the testing of DNA found on the bike. The results came back Wednesday, pointing to Brown.
Already in custody on the gun theft, he racked up even more charges, including first degree murder.
McElroy says detectives served a search warrant Wednesday night at an apartment on Muskogee Court where a witness says he was stashing the evidence. Sure enough, detectives found critical evidence, including a gun, linking Brown to the shooting and two ATM robberies.
Brown showed little emotion during his first appearance in juvenile court this morning as he was ordered to stay in custody.
Police are asking he be charged as an adult for the crimes. The State Attorney's Office has 21 days to make a decision.
Brown, who already had 12 violent felony arrests on his record now faces charges of first degree murder, attempted robbery, grand theft of a firearm, two counts of armed robbery and felon in possession of a handgun.
"This is a problem that we've had and this case is an example of how difficult it can be when a child doesn't get the help he needs and doesn't face serious consequences for his actions," said McElroy.