KNOXVILLE, Tenn. — UPDATE: Tyrone Mack, 18, has been charged with first-degree murder after the death of Alma Matias, according to the Knox County Sheriff's Office.
Mack is also charged with accessory after the fact, tampering with evidence and abuse of corpse, officials say.
Four people are in custody following an investigation into the death of 23-year-old Alma Matias. Her body was located on July 30 by a jogger near the Cove at Concord Park off Northshore Drive in West Knox County.
Deputies with the Knox County Sheriff's Office have charged Jason Young with first-degree murder, arson and theft, warrants show. Jaquaysjha Ryans, Tyrone Mack and Rontrell Allen are charged with helping Young before or after the alleged murder.
According to KCSO warrants pieced together by 10News, Matias' timeline for her death started on July 29 around 5:30 p.m. According to the KCSO warrants, video surveillance shows Matias pulling into the Ridgebrook Apartment complex in Mechanicsville. Warrants said detectives watched surveillance video of Matias entering the apartment rented by Ryans.
"She does at one point go back to her vehicle and comes back to the apartment. She is not seen again leaving the apartment," warrants state.
Inside the apartment, Mack told detectives he heard several gunshots, then saw Young with a gun in his hand, and Matias on the ground, the affidavit of complaint, filed in court said.
KCSO reports said video surveillance shows several people are seen leaving the premises and coming back, driving Matias' car.
Around 10:20 p.m., the affidavit said Ryans moved Matias' car to the side of the complex.
A few hours later, three people came out of the apartment, according to the video surveillance, with something very large wrapped up in a blanket. They placed it in the backseat, court documents said.
Around 4 a.m. on July 30, reports said license plate readers flagged Matias' car driving down Merchant's Road near I-75. They identified Jason Lamont Young as the driver, with Matias nowhere to be seen.
Behind Young, the report said Rontrell Allen was following him in a white Honda.
Both cars pulled into Casey's gas station off Merchants. At that point, video surveillance from the gas station shows Young entering the gas station, paying the clerk and filling a red gas can.
KCSO said cyber investigators identified Young and Allen through facial recognition software.
Both cars left Casey's within ten minutes and are reported to have headed northbound on I-75.
Around 4:30 a.m., KCSO was called to the corner of Heiskell Avenue and Windstone Boulevard, with reports of a car fire. The car on fire belonged to Matias. The gas can, purchased by Young at the Casey's gas station, was positioned next to Matias' burning car, KCSO reports said.
Deputies arrested Allen, who initially said he was home that night. However, after deputies revealed video surveillance, he admitted to chatting with Young that evening.
KCSO said Young turned himself in on charges of arson and theft of property but bonded out. His arrest warrant on those two charges was issued on July 31.
On Aug. 5, the Sheriff's Office issued a warrant for the arrest of Young on first-degree murder charges. KCSO said Young also turned himself in on those charges.
Ryans was booked on Aug. 5 with three felony charges for abuse of a corpse, accessory after the fact and tampering with evidence.
Mack was booked on Aug. 5 with three felony charges for abuse of a corpse, accessory after the fact and tampering with evidence.
"Jaquaysjha Ryans and Tyrone Mack begin the next few hours cleaning the apartment and removing evidence by placing items in their vehicles... they displaced those items at a storage facility in Knox County," the report said.
Makeya Maxwell said Alma Matias was her best friend growing up. Maxwell said she and Matias considered Ryans, Mack and Young friends, and that's why she thinks Matias went to their house.
"I'll never get over this. I will never get over this," Maxwell said. "If I could do anything to save her, I would've."
Matias's family held funeral services for her on Monday evening.