Vermont police say they were called at about 11 a.m. Thursday after receiving a report that 37-year-old Joseph Sylvester, of Claremont, might be near an interstate bridge in Windsor.
Troopers from Vermont and New Hampshire and officers from the Windsor police and fire departments responded.
When the first trooper arrived Sylvester was standing at the edge of the bridge in the southbound lane. He jumped before contact was made.
He was found below on Vermont Route 44. He was declared dead at the scene.
The investigation is continuing.