Emily Rodriguez-Avila's body was found on Sept. 4, more than 50 miles away from work where she was last seen alive.
LIBERTY COUNTY, Texas (KTRK) -- As the investigation continues into the death of a 16-year-old girl, whose body was found more than 50 miles from where she was last seen alive, authorities said there are a few possible motives behind her death.
Kevin Rivera-Ortiz, 19; Joel Garcia-Martinez, 20; and Katherine Alvarez-Flores, 20, have been charged with murder in connection with the death of Emily Rodriguez-Avila.
Alvarez-Flores, who is being held on a $1.5 million bond, was the first of the three to be arrested on Sept. 8 on a charge of tampering with or fabricating physical evidence. Court records show she altered or destroyed a cell phone with evidence on it.
Rivera-Ortiz, whom authorities identified as Rodriguez-Avila's ex-boyfriend, and Garcia-Martinez were arrested Tuesday in Houston. Both were given a $1 million bond.
Several law enforcement agencies are now involved in the case, including the Homeland Security Gang-Unit South and Houston police's gang unit.
"There's indications that there may be some gang activity involved in this. But, at this time, to confirm it would be premature, but it is an aspect they are looking into," Liberty County Capt. Ken DeFoor said.
He said there are motives that investigators are looking into but did not want to release them at this time.
Rodriguez-Avila was identified as the teenager who was found with a gunshot wound the morning of Sept. 4 on the side of County Road 3550, near County Road 5708, on the north end of Liberty County.
The 16-year-old was last seen getting into a friend's car as she left Niko Niko's restaurant on I-10 and the Beltway the night before. Sources said a relative usually picked her up from work, but she told her relative that a friend was picking her up on Saturday. That was the last time anyone saw her alive.
Rodriguez-Avila's body was found the following morning wearing a hairnet, shirt, and blue cap with the business name of "Niko's" on them, the sheriff's office initially said early in the investigation.
Staff at Niko Niko's Greek and American Cafe near Beltway 8 confirmed with ABC13 earlier this month that Rodriguez-Avila was one of their employees. They declined to go on camera but said they were devastated by the news.
Law enforcement involved in the investigation plan to have a news conference this week to provide an update on the case. A date has not been set.
A GoFundMe has been set up to help Rodriguez-Avila's family with expenses.
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