AUGUSTA, Maine (AP) Maine utility regulators have voted to launch a formal investigation of the state’s biggest electric utility in response to an independent audit that uncovered customer service issues.

The Maine Public Utilities Commission voted 3-0 Tuesday to initiate the inquiry at Central Maine Power, which has weathered complaints of high bills in recent months.

Commission spokesman Harry Lanphear said Liberty Consulting’s independent audit did not find a systemic billing or metering problem that would have led to such high bill complaints.

But state regulators support a broader investigation into the audit’s findings, which include issues with customer communication and service. CMP would also be allowed to provide its own analysis.

CMP spokeswoman Catharine Hartnett called the regulators’ approach “reasonable.” She said the utility looks forward to a “full and fair” examination.