SAN ANTONIO – Four men were arrested during a two-day joint operation in Bexar County aimed at combating child exploitation, Sheriff Javier Salazar said during a press conference.

Salazar said the operation was conducted with the United States Secret Service as part of a training class for new investigators from various law enforcement agencies. The practical portion of the class required participants to conduct a real operation, which Salazar said took place on the 26th and 27th of last month.

Salazar said the four arrests involved state charges of online solicitation of a minor, with each suspect accused of communicating with someone they believed was a 14-year-old girl. He said no children were harmed or put at risk because undercover officers were used during the operation.

Those arrested were:

Yudir Nieto Alfonso, 45, charged with online solicitation of a minor, a third-degree felony, Salazar said.Julian Michael Sandoval, charged with online solicitation of a minor, a third-degree felony, Salazar said.John Michael Roberts, 47, charged with online solicitation of a minor. Salazar said Roberts is in the military and he believed Roberts was a reservist.Joseph Mark Littlefield, 35, charged with online solicitation of a minor. Salazar said Littlefield may be familiar because he was arrested in an operation “several months back in April” for similar alleged activity and was out on bond at the time of the new arrest, still wearing an ankle monitor.

Salazar said Littlefield was employed as a firefighter at the time of the April arrest. He said Littlefield was allegedly “conversing with somebody he thought was a young girl, when in reality it was an undercover officer” working with the task force.

“I can guarantee you this guy lost a lot after that first arrest, or at least he should have,” Salazar said, adding, “I’m sure he’s no longer working as a firefighter.”

Salazar said investigators did not have direct information available on which websites were used, but described them as “common sites” and said some may be sites people use daily, while others may be unfamiliar. He urged parents to monitor their children’s online activity and warned that people online may not be who they claim to be.

Salazar also encouraged anyone who recognizes the suspects, recognizes similar activity, or knows of a child who has been victimized to contact the Bexar County Sheriff’s Office at 210-335-6000.

The training class was funded by the Treasury Executive Office for Asset Forfeiture, Salazar said, explaining that forfeited assets can be used to help finance crime-fighting efforts. He said that, outside of the class costs, work with the Secret Service is typically “self-funded activities.”

Salazar said the cases currently involve state charges, but authorities will pursue federal charges if possible to increase penalties.

He also said the sheriff’s office has already begun discussing with the Secret Service how to make the effort a more permanent fixture, citing ongoing need and the likelihood of repeat offenders.