DETROIT, MI — Six Detroit police officers were suspended Tuesday, accused of taking bribes from a towing company owner in exchange for funneling work to the firm.

A police source familiar with the investigation said some of the cars sent to the company by officers were stolen, the Detroit News reports. Detroit Police Chief James Craig would not confirm the details of the FBI probe, but said the officers are expected to be indicted soon. "It's still an active investigation," he said. "This investigation has been going on for some time, and we have our own internal investigation which is ongoing." He added that more officers could be suspended.

The officers have been suspended with pay, pending the outcome of the investigation, Craig said. Protocol calls for officers to rotate jobs to the 23 tow companies authorized to remove vehicles for the police, the News reports. Different companies are assigned specific areas in the city. The police source told The Detroit News the six suspended officers allegedly were paid by one tow company owner to bypass the other firms on the list.

"The FBI Detroit Area Public Corruption Task Force has an ongoing investigation, and we're working in partnership with the DPD internal affairs," FBI spokesman Tim Wiley said. Craig said he was troubled by the accusations against his officers."We take this alleged criminal misconduct seriously," he said. "I've always said: It's troubling when officers make decisions to commit crimes. It tarnishes not just our department, but our entire profession."

Detroit Police Officers Association president Mark Diaz said the officers were suspended for conduct unbecoming an officer, but said he didn't have any further details.

The controversies surrounding the police towing operations have been well-documented. The Detroit Board of Police Commissioners, which oversees towing operations, struggled for years to institute new rules that were fair to all tow companies that do business with the city, after claims of cronyism and corruption surfaced.

Whenever towing was discussed at police board meetings, lawyers for tow companies and owners of towing firms often packed the room. Board chairman Willie Bell said there recently were complaints about the towing process which were being investigated by the police department's internal affairs unit.