Phoenix- Following a week of tough talk, a 250-member sheriff’s posse charged with finding and arresting illegal immigrants made just one arrest in its inaugural desert search early Thursday morning.

The posse, made up of existing sheriff’s deputies and unpaid, trained volunteers, on Wednesday night launched night patrols in desert areas and major roadways southwest of Phoenix.

They’re looking for illegal immigrants to arrest under a state smuggling law that allows local law enforcement to arrest and charge suspected human and drug smugglers with a state-level felony. Smuggling already was a federal felony.

Since March, the Maricopa County Sheriff’s Office has arrested 147 illegal immigrants and smugglers under the law as contentiously interpreted by Maricopa County Attorney Andrew Thomas.

Thomas argues that the smuggling law can be applied to the smuggled immigrants themselves. By paying a smuggler to enter the country, Thomas says an illegal immigrant is committing conspiracy to smuggle, punishable by up to 2 years in jail.

The sheriff’s office announced last week that it would dedicate an entire posse to arresting illegal immigrants under the law.

“We’re going to arrest any illegal who violates this new law,” Arpaio said. “I’m not going to turn these people over to federal authorities so they can have a free ride back to Mexico. I’ll give them a free ride into the county jail.”

At the launch Wednesday night, Arpaio told the sheriff’s posse to not worry about costs or jail space, but to arrest as many illegal immigrants as they found.

Deputies attempted to pull over a pickup truck around 12:45 a.m. Thursday, but the truck took off in the desert and its 15 to 20 occupants scattered.

Only one of them was tracked down despite night vision equipment, spotlights and a helicopter.

To say the least, it was a disappointment.

“It just makes me angry,” Arpaio said Thursday. “People say these are helpless people coming into the United States just to work, and yet when they see law enforcement, they run. If they were trying to obey the law, why are they running?

“That doesn’t make me happy,” he continued. “We didn’t catch anybody else, and I don’t know why.”

Arpaio speculated that the night was slow because potential border crossers have heard that if they’re caught his county, they won’t get very far.

Then again, maybe it was just a slow night, he said. Either way, the posse will continue its patrols for illegal immigrants.

“This isn’t a one-night operation,” Arpaio said. “We’re going to keep going and keep booking them into the county jail. We’re up to 147. I don’t care if we go to 1,000 or 2,000 illegals. We’ll make room for them. I’ve got a lot of tents out there.”

The Center for Human Rights and Constitutional Law in Los Angeles is challenging the application of the smuggling law to illegal immigrants.

“You cannot charge someone with conspiracy to violate a law that inherently involves two people, because then you could just charge every single person involved with conspiracy,” said Peter Schey, president of the human rights group. “Say you have an adult participating in consensual sex with a 16-year-old. You can’t charge the 16-year-old with conspiracy to commit statutory rape.”