At least 10 construction workers were injured when part of an onramp bridge that is under construction on the 91 Freeway in Corona collapsed late Friday, officials said.
The incident occurred about 11 p.m. as workers were lowering a section of the bridge into place at East Grand Boulevard when the jacking operation failed, according to a statement from the Riverside County Transportation Commission.
The failure caused the bridge deck to drop about 16 inches and hit wooden support beams, which in turn struck the workers, according to the statement.
All the injured workers were transported to local hospitals. Their conditions were not immediately known.
Beatrice Espinoza, an 82-year-old resident who lives nearby, said she heard the bridge collapse.
"We heard the bang that we all thought was an earthquake," she said. "The first thing that comes to mind is that this was an earthquake."
She said she went outside to see what happened.
"There were sirens all over the place," she said. "It was horrible … and the ambulances were all lined up."
She said she saw firefighters go into the accident scene to retrieve injured workers on stretchers.
"It was terrible," she said.
East Grand Boulevard is closed indefinitely, but the 91 Freeway remains open.
The freeway construction is part of the 91 Project, which includes adding regular and tolled express lanes on the freeway.
There will also be auxiliary lanes and direct express lane connectors between the 91 and 15 freeways.
The new lanes are expected to open in 2017.