Witness: Japan quake a "terrifying sensation"

The largest earthquake in Japan's recorded history created a "terrifying sensation" for witnesses on the ground.

Speaking to CBS' "The Early Show," Matt Alt, an American living in Tokyo for the last eight years, described Friday's ordeal.

Complete Coverage: Earthquake in Japan

"Oh, it was a terrifying sensation. The only way I could describe it [is] like a sustained sense of vertigo," Alt said over Skype. "The entire floor was shaking almost like a carnival ride or something like that. Only you never knew when it was going to stop. And it only lasted for about a minute or so, but I can tell you, it felt a lot longer than that."

Pictures: Quake, tsunami slam Japan

Authorities said at least 60 people were killed and 56 missing after the magnitude 8.9 offshore quake unleashed a 23-foot tsunami. The quake was followed by at least 19 aftershocks, most of them of more than magnitude 6.0. The death toll was likely to continue climbing given the scale of the disaster.

Alt said he and his wife went outside their home as the quake hit.

"It was so strong, and the undulation of the earth was so powerful that we actually had to kind of hang onto the outside of our house, and eventually we had to crouch down almost like in a little ball to keep from falling over."

Raw video: Japan tsunami tosses ships

Dozens of cities and villages along a 1,300-mile stretch of coastline were shaken by violent tremors that reached as far away as Tokyo, hundreds of miles from the epicenter.

"The earthquake has caused major damage in broad areas in northern Japan," Prime Minister Naoto Kan said at a news conference.

Raw Video: Japan tsunami sweeps away cars, homes

Alt said that Tokyo was "very fortunate in that it's a very technologically advanced sort of place. And there are a lot of systems here in place to lessen the impact of earthquakes. So although there are sporadic fires, and there's a lot of issues in the city, for instance the trains have been stopped, and a lot of people are stranded downtown, but actual damage is fairly minimal, which ... we're all very grateful for. It's up north where the real devastation is."

He also said he expects citizens to be on edge for the rest of the night.

"It's going to be kind of a dicey evening, I think. Darkness has fallen over the city right now, which kind of adds this whole new layer to this. And there have been regular aftershocks. There were four major ones immediately after the first tremor. And then, uncountable small ones. And so I think a lot of people are going to be sleeping with their jackets and their shoes near their beds tonight just in case they have to make a hasty exit."