By Susan Montoya Bryan, Associated Press New Mexico's top prosecutor has opened an inquiry into utility costs during a winter blast that plunged New Mexico and other states into a deep freeze. State Attorney General Hector Balderas says the weather emergency caused tremendous damage and he wants to ensure New Mexicans won't be further harmed by skyrocketing bills. His office set a deadline of Friday for utilities to provide analyses of customer impacts and options for addressing the potential price shock. The utilities also are being asked to explain to their customers the circumstances and the steps being taken to mitigate the situation.