Two lanes of I-95 north were closed between Exits 9 and 10 after the accident, which occurred just before noon, according to the Connecticut Department of Transportation. (All lanes had been closed immediately after the incident.)
The on- and off-ramps are also closed at Exit 9, according to DOT and state police.
State police urged drivers to reduce speed as first responders investigate the "untimely death" in the area.
The accident occurred just before noon near the Courtland Avenue overpass in the vicinity of Exit 9, DOT said.
Traffic is tied up for nearly 6 miles back to Exit 4, DOT said at about 12:45 p.m. Thursday.
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