A tractor-trailer carrying canisters of volatile hydrogen gas crashed on a major East Coast route early Tuesday, forcing responders to close the road and evacuate dozens of homes.

Compressed hydrogen gas leaked from some of the containers after the truck rolled on its side in the median around 5:30 a.m. on Interstate 84, state police said.

The truck driver was slightly injured and taken to a hospital, authorities said. No other injuries were reported, and the cause of the crash was being investigated.

Both sides of the road were shut for most of the day, snarling traffic for miles on local roads that soon became choked with cars.

U.S. Rep. Rahm Emanuel of Illinois, a high-ranking Democrat, got stuck in the traffic while traveling from New York to Hartford for a fundraiser for Connecticut Rep. Joe Courtney.

"We're just in one long snake line here," he told reporters.

The highway was expected to remain closed through the evening rush hour, said Lt. J. Paul Vance, a state police spokesman. Complicating matters was a snowstorm forecast through the night.

A Massachusetts company was called in to take care of the hydrogen canisters. The firm will empty out the canisters, "and hopefully that will make the salvage operation safe," Vance said.

Sixty to 70 people fled their homes and were taken to a shelter at the Middlebury Fire Department, said Middlebury Police Chief Richard Guisti.