St. Louis ? Top leaders in Missouri and Illinois, where thousands of customers remain without power after last week’s winter storm, sharply criticized a utility’s response to the crisis Thursday.

Missouri Gov. Matt Blunt asked his state’s Public Service Commission to have public hearings and said he wants St. Louis-based Ameren Corp. to provide a clear plan for preventing a recurrence.

“People that are paying the utility bill deserve to have the consistent delivery of services,” Blunt said at a news conference in Jefferson City. “That’s not happening with Ameren today.”

As of Thursday evening, about 22,000 Ameren customers still lacked power, all but about 670 of them in Illinois, spokesman Tim Fox said. At the peak, more than 500,000 Ameren customers in both states were without power.

Illinois Lt. Gov. Pat Quinn also pressed utility regulators to investigate, calling the lingering power disruptions a “systemic failure” despite the efforts of thousands of repair workers from 14 states.