LIBERTY, Texas (KIAH) — All three people who are accused of murdering a 16 year old girl in Liberty County in early September have confessed to the crime — and one of them used to be in a romantic relationship with the victim.

Those are some of the new details in the case that were revealed Friday afternoon during a news conference at the Liberty County Sheriff’s Jail Division Annex Building.

Captain Billy Knox, the head of the sheriff’s office’s Criminal Investigation Division, spoke to several members of the media with representatives from the Liberty County District Attorney’s Office, Houston Police Department, and Texas Rangers behind him.

He said that Emily Rodriguez-Avila voluntarily got into a car with three people she knew after getting off of work at a Niko Niko’s restaurant in west Houston on the night of September 3.

One of the other people was Kevin Rivera-Ortiz, 19, with whom she’d previously had a romantic relationship Knox said.

Joel Garcia-Martinez, 20, and Katherine Alvarez-Flores, 20, were also in the car Knox said, and that all three were there when one of them shot Rodriguez-Avila once in the side and once in the head.

Someone called the sheriff’s office after finding her body near the intersection of Liberty County Roads 3550 and 5708 in the Cleveland-area on the morning of September 4.

Four days later, after tracking down some of the victim’s friends, investigators questioned Alvarez-Flores — charging her with tampering with or fabricating physical evidence at that point.

On September 10, Knox said that she confessed to her role in Rodriguez-Avila’s death and they charged her with murder.

Then, on Tuesday, Houston Police Department SWAT officers arrested Garcia-Martinez and Rivera-Ortiz at separate locations in the city — both of whom Knox says are in the country illegally.

Knox said they too confessed to the crime, but all three told different stories about why the killing happened, and those details are not being released.

They remain in the Liberty County Jail on a million dollars bond on the murder charges.

Alvarez-Flores has an additional $500,000 bond for the tampering charge.

Knox credited the arrests to good teamwork among the law enforcement agencies involved.

He also asked everyone to keep Rodriguez-Avila’s family in their prayers.

“It’s an unfortunate situation,” Knox said. “We have a 16 year old girl who’s not going home to her family and just violently murdered.”