Power outages caused disruption to AT&T's cell phone and mobile data service in parts of the midwest AT&T on Monday said it had restored service after power outages and bad weather caused its service to go down in parts of the United States.A power failure hit an AT&T facility in Bloomfield, Mich., on Sunday morning local time, which caused mobile service disruption in parts of the midwest region of the United States, the company said on Sunday.[ Get the latest on mobile developments with InfoWorld’s Mobile Report newsletter. ] Though most services were back up on Sunday, AT&T said some customers may have experienced “sporadic service issues” on Monday as it “rebooted equipment impacted by power outages,” the company wrote on its Twitter page. However, as of a few hours ago, AT&T said it had fully restored services.Frustrated AT&T subscribers on Sunday reported cell phone and data services being affected in multiple states and major cities such as Chicago from the outage. Some users also reported not being able to access AT&T’s data network using Apple’s iPhone or Research In Motion’s BlackBerry mobile devices.“As I write this, some 10 hours after the outage began, I don’t have many facts other than my Blackberry didn’t work for about 9 hours today,” wrote blogger Matt Friedman on the Tanner and Friedman blog. AT&T did not respond to request for comment about the outage. Technology IndustrySmall and Medium Business