Norwich — Four people were taken to the hospital this afternoon following a multi-vehicle accident involving a tractor-trailer carrying liquid nitrogen that closed the southbound side of Interstate 395 for about an hour, fire officials said.

First reported at 4:16 p.m., the crash occurred between exits 83 and 82. Emergency responders from the Occum and Yantic fire departments joined state police at the scene and found five vehicles involved.

One person had to be extricated from a vehicle because of the heavy damage, according to Occum Deputy Fire Chief Bob LaChapelle.

“Our biggest concern was for the patients and the tanker,” he said.

The tanker, registered to Airgas, was not breached and a minor coolant leak was quickly contained, LaChapelle said. Patients were transported to The William W. Backus Hospital by American Ambulance.

The crashed led to traffic congestion in the area.

State police are investigating the cause of the crash and have not yet released further details.