Arizona officials on Monday reopened the investigation into a deputy's explanation of how he was shot in the remote desert south of Phoenix amid speculation it was a hoax timed to enflame the debate over illegal immigration.

The Pinal County Sheriff's Office announced its decision Monday after two nationally known forensic pathologists raised questions about a wound the deputy suffered in a Phoenix New Times story, and then later to other media outlets.

Pinal County Deputy Louie Puroll told investigators that he was following a group of smugglers carrying bales of marijuana April 30 when he was ambushed by men firing AK-47 rifles. In what Puroll described as a running gunbattle, he was grazed by a bullet in the back.

The pathologists, Dr. Michael Baden of New York and Dr. Werner Spitz of suburban Detroit, examined photos of the wound released by the sheriff's office. They told The Associated Press on Friday that they concluded the bullet was fired from inches away, not from at least 25 yards away as Puroll said.

The sheriff's office soon after released a statement saying it stood behind the official investigation, and that physical evidence supports the deputy's account.

But the office reopened the case Monday, saying it wants to maintain transparency.

Pinal County Sheriff Paul Babeu told The Associated Press that the shirt Puroll was wearing the day of the shooting is being sent to the state Department of Public Safety for testing. The department will check for gunshot residue, charring, burning or any other evidence that it was a close-range shot.

"Clearly we don't have anything to hide," Babeu said. "If you think, 'Oh my God, this is the smoking gun,' we're going to send it to an outside agency and they're going to tell us."

Babeu said the shirt wasn't sent to DPS originally because his office never had any indication that Puroll wasn't telling the truth, and all the evidence backed up his story.

He said Puroll thanked him for reopening the case so he can be vindicated and get back to his normal life.

Puroll is back to performing his normal duties, but Babeu said he's been "dragged through the gauntlet of public scrutiny."

On Friday, the sheriff's office said Friday there were no burn marks on Puroll's shirt and that his wound had no stippling, which is caused from burnt gunpowder coming from the barrel of a gun fired at close range.

But Baden said Puroll's shirt did appear to have powder burns.

The sheriff's office said Monday it consulted with Dr. Phil Keen, former chief medical examiner for Maricopa County, about the other pathologists' opinions. He said Keen disagreed but that he would need the results of tests on the shirt to confirm his opinion.

Puroll's shooting fueled an already blazing debate in Arizona and the nation about the dangers of immigrant and drug smugglers in southern Arizona. It came just days after Arizona Gov. Jan Brewer signed a sweeping law giving law enforcers powers to question suspected illegal immigrants and arrest them. The major parts of that law have been put on hold by a federal judge on constitutional grounds.

The shooting immediately raised questions about a deputy supposedly looking for armed drug smugglers in the remote desert without backup. A dragnet involving more than 100 officers in the rugged mountainous area about 50 miles south of Phoenix found no suspects and no bales of marijuana.

The area is a well-known smuggling corridor for drugs and illegal immigrants headed from Mexico to Phoenix and the U.S. interior.

(This version CORRECTS Corrects governor's first name to Jan.)