Updated at 3:35 p.m. ET -- A commuter ferry packed with more than 300 passengers crashed into a dock in Lower Manhattan early Wednesday, injuring 74, at least two critically. Nine people were also in serious condition, officials said.

The force of the crash tossed some morning commuters in the air and sent others tumbling down stairs, witnesses said.

“Everybody got jolted right out of their seats,” passenger Sean Boyle told NBC 4 New York, adding that it felt like the vessel went "full speed right into the pier.”

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After the accident, a large gash could be seen in the underside of the ferry, which was operated by Seastreak and originated from Highland, N.J., around 8 a.m.

Aerial footage showed people strapped to stretchers, their heads and necks immobilized, with firefighters swarming the ferry and surrounding areas.

“We were pulling in like we normally do every day, and the next thing I know, I was six feet in the air,” rider Ashley Furman told NBC 4 New York.  “I woke up from getting knocked out six feet in the air behind me. Thank god I’m OK and I’m not on a stretcher like everybody else.”

One of those in critical condition was rushed to surgery with a head injury, a spokesperson with the New York Police Department said. A total of 326 people, including five crew members, had been aboard the vessel.

It was not known what caused the crash, which occurred at Manhattan's Pier 11, near Wall Street. Weather conditions were normal Wednesday morning, and no mariner warnings had been posted before the 8:45 a.m. accident happened, NBC 4 New York reported.

According to James Barker, Seastreak’s president, the ferry’s captain was at the controls when the vessel crashed. Barker said the captain had passed a breathalyzer test, and authorities were still waiting for results of a drug test – both of which are routine tests to be taken in accidents such as this one, according to the U.S. Coast Guard.

He added that the captain, a 10-year veteran of Seastreak, was cooperating with authorities.

The National Transportation Safety Board launched a full investigation into the crash, and was working with the Coast Guard.

Seastreak commuter service offers rides from the New York metropolitan area to and from New Jersey, according to its website.

Wednesday's ferry accident was not the only one in recent New York history. In 2003, a Staten Island ferry got into an accident when its pilot, suffering from fatigue and on painkillers, passed out at the wheel; 11 people were killed. In May 2010, due to a mechanical malfunction, the same ferry smashed into a pier, injuring nearly 40 people. 

PhotoBlog: Pictures from the ferry accident in Lower Manhattan

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A commuter ferry crashed into Pier 11 in Lower Manhattan on Wednesday, injuring dozens.