A federal jury convicted a man of kidnapping and conspiracy on Thursday in a case authorities said showed he was member of a south Texas kidnapping ring controlled by the Mexican Gulf cartel.

Luis Avila Hernandez was convicted on charges related to the August 2008 kidnapping of Daniel Ramirez Jr. from his job at a convenience store in Weslaco.

The jury deliberated for about 1 1/2 hours before returning its verdict. Sentencing was scheduled for March and Avila could face life in prison.

Co-defendants in the case had testified that Ramirez was eventually killed after being held in Reynosa, Mexico, in spite of a $40,000 ransom paid by his family. Trial testimony suggested Ramirez was targeted because the Gulf cartel's enforcement arm, the Zetas, were trying to expand their influence over those involved in the drug trade on the U.S. side of the border.

Avila's attorney, Jose Luis Ramos, attacked the credibility of the government's witnesses, some of whom had reached plea agreements with prosecutors.

"Are you willing to convict someone on the word of these scoundrels?" Ramos asked jurors in his closing argument Thursday. Following the verdict, Ramos said he still doubted the accuracy of some of the prosecution's evidence, but said the jury must have seen it differently.

"It was a bad crime, what can I tell you?" Ramos said.

Assistant U.S. Attorney Robert Wells Jr. conceded in his closing remarks that some prosecution witnesses were not upstanding citizens, but offered that such people would not be the ones with information about the kidnappings.

Prosecutors also reminded jurors that Avila had admitted his own role in the kidnapping ring when he gave his initial statement to investigators.

Wells said the goal of the kidnappers, who acted on orders from Jaime Gonzalez Duran, a founding member of the Zetas now on trial in Mexico on organized crime charges, was to make south Texas run like Mexico.

"This is about greed," Wells said. "This is about money. And whoever gets in the way is going to get punished."