Updated

BOSTON -- A tour boat with 174 people on board ran aground on a rocky ledge in Boston Harbor on Saturday and began taking on water, authorities said, and it was evacuated.

The Coast Guard said two people reported back and knee injuries after the accident, which happened at about 10 a.m. off Deer Island.

By early afternoon, 168 passengers and six crew members had been safely taken off the Boston-based 87-foot vessel, The Massachusetts, said Coast Guard Petty Officer Connie Terrell.

Passengers were being taken to a pier in Hull, about three miles from the disabled boat, she said.

Meanwhile, workers on board The Massachusetts tried to pump out the sinking vessel, while divers attempted to patch the gash in the hull, said Winthrop Deputy Harbormaster Chuck Evans, who was at the scene.

Evans said the boat's operators reported that they collided with a rocks at Devil's Back Ledge while traveling at about 18 knots. The boat was listing heavily toward its bow early Saturday afternoon and its back end had lifted out of the water, he said.

"It's a pretty serious accident," Evans said. "Once it goes down, it would be a total loss, I believe. ... They're trying to save it."

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