PHILADELPHIA (CBS) — An exclusive CBS I-Team Investigation has revealed 20 Philadelphia police patrol cars are now being repaired for cracks in their frames.

City and GM officials confirming they have been working together to make sure problems with the cars, all Chevy Impalas, are corrected.

Fraternal Order of Police officials expressed concern for the safety of officers driving the vehicles.

So far, there have been no reports of any accidents or injuries involving the cars with frame problems.

GM officials responding to an inquiry from CBS 3 stated: “We are aware of the issue involving Chevrolet Impalas operated by the Philadelphia Police Department and have been working closely with them to understand it. We appreciate the time that Department officials have spent with us on this, and we will stand behind our product. We have identified a repair procedure and are working with the Department to implement it in order to ensure continued safe operation of these vehicles.”

City officials tell CBS 3: “The City has been in contact with General Motors which has been very responsive and is working toward a solution with the City. Our office of Fleet Management noticed a problem and contacted GM who promptly investigated. We have since collaborated to work out a solution. In the coming weeks we will repair the vehicles.”

Sources estimate there are approximately 400 Impalas in the city’s police fleet.

For now, many details about the cracked frames remain unknown, including what caused the problem.

Reported By: Walt Hunter, CBS 3