CANTON, Ill. (AP) — Authorities say three properties, including a historic Opera House, have been condemned a day after a natural gas explosion in the central Illinois city of Canton that killed a utility worker.

Canton Police Chief Rick Nichols said at a news conference Thursday afternoon that the Opera House was damaged beyond repair.

Nichols says 48 other buildings in the downtown area were damaged but can be fixed.

Ameren Illinois spokesman Tucker Kennedy says a third-party contractor for a communications company was installing a fiber-optic cable when a tool broke the gas line.

The explosion killed Ameren worker Arturo Silva Jr. of Mapleton, who was on a crew called to repair the line. Three other Ameren workers and several other people were injured. Officials have said the other injuries are not life-threatening.

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