A 25-year-old Corpus Christi man has been found guilty on charges of sex trafficking of a child as young as 14 years old back in May.

According to acting U.S. Attorney Abe Martinez, Marcus Anthony Tunchez had a one-day trial on Dec. 14 before U.S. District Judge Nelva Gonzales Ramos. A verdict came back guilty late Monday.

The case stemmed from a joint investigation targeting gang members in the Corpus Christi area who were suspected of narcotics trafficking and sex trafficking of children. Tunchez was identified as a suspect and member of the Mexican Mafia, and was involved in both methamphetamine distribution and sex trafficking.

Back in September, 3News obtained an affidavit detailing the investigation leading up to Tunchez arrest.

RELATED: AFFIDAVIT: Man charged with attempted sex trafficking of a 14-year-old

It was back in May when Corpus Christi police said Tunchez began selling methamphetamine to an undercover officer. He also told the officer that he could "pimp" several young women, explaining the process of advertising on a commercial sex website for young women who would give Tunchez half the proceeds from commercial sex acts.

Later in September, Tunchez met with the undercover officer for the purpose of sex trafficking a girl who he believed was just 14 years old. He expected to meet the girl and take her to a hotel where she would then provide commercial sex acts to customers for money. Tunchez expected a 20-percent return on her work.

It turned out, the girl was also an undercover officer, and Tunchez was taken into custody upon arrival at their designated meeting place.

Officials said during his trial Tunchez tried to convince the court that he was planning to rob the undercover officer and not commit the sex trafficking crime. Judge Ramos didn't buy it and found him guilty as charged.

As for the narcotics distribution charge and an unrelated gun charge, Tunchez plead guilty to both on Dec. 7.

Tunchez now faces up to a minimum of 10 years to life in federal prison and a possible $250,000 fine. After completing his prison sentence, he also faces a maximum of life on supervised release, during which the court can impose a number of special conditions designed to protect children. He also faces up to 40 years for the drug charges and another 10 for the firearms offense.

Sentencing will be held at a later date, officials said.

The investigation was conducted by Immigration and Customs Enforcement's Homeland Security Investigations and the Drug Enforcement Administration with the assistance of the Corpus Christi Police Department's Internet Crimes Against Children Task Force.

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