A dozen Army and Marine recruiters who visited high schools were among the personnel caught in a major FBI cocaine investigation, and some were allowed to keep working while under suspicion, a newspaper reported Sunday.

None of the recruiters was accused of providing drugs to students.

The recruiters, who worked in the Tucson area, were targets of a federal sting called Operation Lively Green, which ran from 2001 to 2004 and was revealed last year. So far, 69 members of the military, prison guards, law enforcement employees and other public employees have been convicted of accepting bribes to help smuggle cocaine.

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The Arizona Daily Star reviewed the investigation and court documents and found that the FBI allowed many recruiters to stay on the job even though they were targeted by the investigation. Some were still recruiting three years after they were photographed running drugs in uniform, the newspaper said.

Most of the recruiters pleaded guilty and will be sentenced in March. Some honorably retired from the military.

The sting began after the FBI received tips that a former Army National Guardsman was taking bribes to fix military aptitude tests for recruits, FBI Special Agent Adam Radtke said.

Military officials say they kept the recruiters on the job because the FBI told them to leave the suspects alone to avoid jeopardizing the sting. The military said it also didn't know some recruiters were under investigation, the newspaper reported.

Military officials say the criminal acts by recruiters were rare out of the thousands of recruiters working across the country. "This was an isolated incident," said Marine Corps recruiting spokeswoman Janice Hagar.

A governing board member of the Tucson Unified School District, Judy Burns, criticized the FBI for allowing the recruiters to stay on the job so long.

"It's ludicrous to me that the FBI would leave these people in place and allow them onto our high school campuses," Burns said.

Special Agent Deb McCarley said the FBI generally performs risk assessments before deciding to keep suspects who work in public positions on the job during undercover investigations.

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