The FBI has paid employees at the Best Buy's Geek Squad repair unit to act as informants so they could search for illegal content on customers' devices, according to documents obtained by the nonprofit digital rights group Electronic Frontier Foundation.

Electronic Frontier Foundation argued the FBI's use of Geek Squad technicians as informants to search customer's computers could be a violation of the Fourth Amendment.

The relationship between Best Buy and the FBI came to light after a Geek Squad technician in California found a child pornography on the computer of a doctor who sent in his computer to Best Buy for repairs and then alerted the FBI.

U.S. District Judge Cormac Carney dismissed the child pornography charges against the doctor in November 2011 after he ruled that the evidence discovered was an illegal search.

Electronic Frontier Foundation then filed a Freedom of Information Act lawsuit last year to know the extent of the FBI's relationship with the Best Buy after the FBI denied the group access to records.

Documents obtained by the nonprofit reveal that Best Buy officials have been helping the FBI for at least 10 years. An FBI memo showed that Best Buy hosted a meeting at its Kentucky repair facility in 2008 for the FBI's "Cyber Working Group." The memo revealed that Geek Squad employees gave FBI officials a tour of the facility before their meeting.

The FBI's Louisville, Ky., division "has maintained close liaison with the Geek Squad's management in an effort to glean case initiations and to support the division's Computer Intrusion and Cyber Crime programs," the memo said.

Documents acquired by Electronic Frontier Foundation show that when Geek Squad employees found child pornography on customers' devices, they would call FBI agents, who would come to the Best Buy repair facility and then seize the device and send it to an FBI field office near where the owner of the device lived.

The FBI said it won't comment about its relationship with Best Buy "as this pertains to an ongoing legal matter."

"The FBI does not provide any information on the dealings with informants, for obvious reasons," the agency said.

Best Buy said in a statement that its Geek Squad repair employees found "what appears to be child pornography on customers' computers nearly 100 times." The technicians do not actively search illegal content on customers' devices, it said, but they "inadvertently discover it when attempting to confirm we have recovered lost customer data."

"We have a moral and, in more than 20 states, a legal obligation to report these findings to law enforcement," said the Richfield-based company. "We share this policy with our customers in writing before we begin any repair."

"In the wake of these allegations," it continued, "we have redoubled our efforts to train employees on what to do — and not do — in these circumstances."

Best Buy said four of its employees may have received payment from the FBI after they turned over alleged child pornography to the agency. Three of the employees are no longer with the company and the fourth has been reprimanded and reassigned.

One of the documents show that a Geek Squad technician has received a $500 payment from the FBI, something Best Buy said showed poor judgment and was "inconsistent with our training and policies."