(SKAGIT COUNTY, Wash.) -- A portion of an interstate highway bridge in Washington state collapsed Thursday night, sending cars and people into the water, authorities said.
The collapse occurred on the Interstate 5 freeway over the Skagit River in Skagit County, Wash., about two hours north of Seattle.
"N/B and S/B lanes of I-5 Skagit River Bridge collapsed," Washington State Trooper Mark Francis posted on Twitter, shortly after the 7 p.m. collapse. "People and cars in water."
Three people were injured during the collapse. Two people rescued from the water, who were taken to Skagit Valley Hospital in Mount Vernon, Wash., were suffering from hypothermia.
Officials were looking into reports of an oversized load "immediately" causing the collapse, said Travis Phelps of the Washington State Department of Transportation and Washington State Patrol.
"We're looking at the cause being an oversized, over-height vehicle, striking critical portions of this bridge, causing it to collapse," he said.
The National Transportation Safety Board said they will send a team to investigate the collapse.
Clean up efforts will take several days to weeks, according to Phelps. The bridge sees 77,000 cars per day, and Phelps said they are expecting significant congestion until the bridge is fixed.
"We inspect our bridge every two years. We're not going to let anybody drive on a bridge that is deemed unsafe," Phelps said.
The bridge was last inspected in November 2012 and deemed safe, Washington State Department of Transportation spokesman Bart Treece told ABC News.
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