CINCINNATI (AP) - Transportation authorities say southbound lanes of Interstate 75 through Cincinnati will be shut down for days after a closed overpass exit ramp collapsed onto the highway, killing one person and injuring another.

Work was going on Monday night to remove an overhead ramp that had recently been replaced by a new one when it pancaked down on top of southbound lanes several miles north of the Ohio River.

Ohio transportation officials say the interstate will be closed at least 48 to 72 hours.

Authorities have many tons of concrete, steel and other debris to remove and must inspect for pavement damage.

Commuters to downtown Tuesday morning were diverted to Interstate 71 south, while motorists headed to Kentucky could take the Interstate 275 loop around the city.

The Cincinnati Fire Department said the collapse onto southbound interstate 75 happened near Hopple Street north of downtown at about 10:30 p.m. Monday.

Police Chief Jeff Blackwell called it a workplace accident, saying crews were taking down the old bridge when something went "terribly wrong."

"The big-rig driver is very lucky; in a matter of seconds his fate would have probably been different," Blackwell said.

The driver was taken to the University of Cincinnati Medical Center with minor injuries.

Fire officials said the tractor-trailer struck the collapsed section as the bridge hit the ground. They said the construction worker was killed in the collapse. His name was not immediately released.

Blackwell said the city will work with the Department of Transportation to figure out what happened.

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