BOSTON – A tour boat headed on a whale watch with 174 people on board was evacuated Saturday after it ran aground on a rocky ledge in Boston Harbor and began taking on water.

No one was seriously hurt in the accident, which was reported at about 10 a.m. off Deer Island. The Coast Guard said two people suffered back and knee injuries.

Authorities said a combination of Coast Guard vessels, local emergency vessels and nearby fishing boats helped evacuate the 87-foot vessel Massachusetts, and by early afternoon, everyone was safely off the boat. Passengers were taken to a pier in Hull, about 3 miles from the disabled boat, said Coast Guard Petty Officer Connie Terrell.

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.

Evans said the boat’s operators reported that they collided with rocks at Devil’s Back Ledge while traveling at about 18 knots. The boat was listing heavily toward its bow Saturday afternoon and its back end had lifted out of the water, he said. Passengers described a loud noise and a sudden jolt that snapped the legs on plastic deck chairs and sent people sprawling.

“We were physically thrown forward,” Maria Patane of Yonkers, N.Y., told The Boston Globe. “Kids were crying, people screaming.” The Massachusetts is owned by Massachusetts Bay Lines of Boston, which also runs party and harbor cruises. the accident.