TRINIDAD, Colo. (AP) — State transportation officials have opened a detour across the Purgatoire River on Colorado Highway 12, after a crack developed in the bridge over the river.

The Colorado Department of Transportation closed the bridge Wednesday after a crack developed and a two-foot section of concrete broke off. There were no injuries. A one-lane gravel detour parallel to the bridge opened Friday.

The bridge, built in 1925, was being replaced when it failed. The detour will remain until the new bridge opens. That is currently scheduled for October.

Engineers are still trying to determine what caused the bridge failure.

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