MANATEE COUNTY, Fla. (WFLA) – Nearly 15 years after a teenager’s body was found on the side of a Florida road, authorities say they have made three arrests in her killing.

Ralph Williams, 36, Tyjuan Williams, 32, and their half-brother, Jamaine Brown are being held over the 2006 murder of 16-year-old Amber Woods.

Deputies said Woods was last seen alive by her aunt around midnight on Feb. 21, 2006. Later that morning, she was found shot to death off State Road 62, about three miles from the Hardee County line.

Investigators had been told Woods was dating Ralph Williams and believed she was pregnant with his child. They obtained a text message from Williams showing that he was concerned about her “pregnancy” because Woods was underage. He allegedly conspired with his brothers to kidnap and kill her. An autopsy showed Woods was not pregnant.

Investigators conducted dozens of interviews, but the case went cold without enough evidence.

It was finally cracked with the help of previously unavailable cell phone tracking software, which placed a phone used by Ralph Williams near the area where Woods’ body was found on the night of the murder.

In May, detectives obtained a warrant for Brown’s arrest, accusing him of kidnapping Woods. In a recorded interview, detectives say Brown confessed to kidnapping Woods and driving her to a rural location with his brothers. He said Tyjuan shot her once in the back, and he and Ralph dragged her body into high grass.

Ralph Williams and Tyjuan Williams were both charged with second-degree murder on Tuesday. The sheriff’s office said both men were already in jail on unrelated charges in Polk and Hardee counties. They will stay at those facilities without bond, awaiting extradition.

Brown pleaded to a charge of accessory after the fact to murder. He remains at the Manatee County Jail.