Groton — A tractor-trailer driver died Tuesday morning after driving off the left side of Interstate 95 south and down an embankment just past Exit 89, state police said.

Police, who did not identify the driver, said the tractor-trailer came to a stop on Cow Hill Road.

Members of the Old Mystic Fire Department said the crash brought down wires in the area, prompting a response from Eversource.

The state police crash reconstruction team and truck squad were on scene. Members of the state Department of Energy and Environmental Protection were helping Old Mystic firefighters clean up.

Officials expected Cow Hill Road to be closed between Bindloss and Oral School roads "for an extended period of time."

Crews also closed the left lane of I-95 to do road work around 9 a.m., the state Department of Transportation said. The work was expected to last until 3 p.m.