Two tractor-trailers plunged into the water along I-84 on the Ashford-Union town line after colliding early Thursday morning, according to state police.
The trucks were traveling on I-84 East just before 2 a.m. when the crash happened.
Both trucks went into a pond and were at least partially submerged in the water, state police said.
The Tolland County Dive Team responded to the scene.
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One person died in the crash, according to the Connecticut Department of Transportation.
I-84 East was closed for several hours, but one lane has since reopened.
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