(CNN) -- A luxury cruise line ship collided in deep fog with a container ship off Vietnam, punching a hole in the container ship and knocking passengers off their feet, a passenger told CNN Monday.
"The foghorn at the back of the ship had been going off consistently, throughout the morning," passenger Andrew Lock said Monday from Hong Kong about the incident, which occurred Friday morning, when the Silver Shadow was about five miles from the coast.
"But there was a certain point in time when the foghorn at the front of the ship suddenly sounded. And it was much much louder. And it caused us to look up. And in fact we looked up straight out of the window. And through the fog, to our horror, we saw this Vietnamese container ship appear, sideways on. And it was as if our ship was perfectly lined up to hit it in the side. So, it was a horrifying moment. And in less than about five seconds after the ship appeared. We did in fact collide right in the side of it."
Lock said he and his wife had braced themselves for the impact and stayed upright. That was more than could be said of the other vessel. "The Vietnamese ship rolled over -- at a 90-degree angle. In fact, we thought it was going to capsize. It then righted itself. And with the forward momentum of our ship, it pushed the Vietnamese ship around, so that it actually came down the side, the length of our ship, scraping along the side as it went. And from that viewpoint, we could see just how much damage had been done to THAT ship, and it was substantial."
He said he was aware of no injuries aboard the luxury vessel, which had a hole dug in its bow, but said the other vessel was badly damaged. "We struck the other ship in several places that we could see -- we struck it at the bridge, where they would operate from. We literally crushed the ship inwards. And we also struck the sides of the ship, causing a tear along the side, a vertical tear, quite substantial. And as we passed by the other ship, I personally saw several of their crew members just lying on the deck."
After the impact, he said, passengers gathered a few of their possessions and headed to the muster stations. "The crew was calm, but the passengers -- some were scared, or even frantic," Lock said.
But after about 10 minutes, the captain announced that there was no imminent danger, he said.
The ship went on to anchor in Ha Long Bay, as had been planned. "The next day, we went to a nearby port and once we were off the ship we could see how extensive the damage was," Lock said.
In a statement, Silversea Cruises said the Silver Shadow "was involved in a minor incident on March 16, 2012, at around 4:20 GMT as it was approaching the pilot station in Ha Long Bay, Vietnam. There was contact between Silver Shadow and a local commercial vessel. Silver Shadow incurred limited minor dents and guests' safety was never compromised. The ship was fully operational and continued on its course to Ha Long Bay, where all shore tours operated normally."
Lock disputed the cruise line's characterization of the incident. "It was a major collision," he said.
Silversea said it will carry out a full investigation into the incident.
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