(CNN)– At least nine people died when an earthquake struck Japan late Thursday, reported state broadcaster NHK, citing police officials.

Search crews scrambled to dig through rubble in southern Japan, looking for people trapped under collapsed buildings Thursday night.

The magnitude-6.2 quake struck near Ueki, the U.S. Geological Survey said. Dozens of smaller aftershocks followed.

“The ground shook for about 20 seconds before the 6.2-magnitude quake stopped,” witness Lim Ting Jie said.

Two deaths occurred in Mashiki, the Kumamoto Prefecture Disaster Management Office said. One person died in a collapsed house, and the other died in a fire caused by the quake.

At least 135 people were hospitalized in Kumamoto, city officials said.

Gen Aoki, director of the Japan Meteorological Agency’s earthquake division, warned more aftershocks could occur over the next week.

“This is an earthquake that is going to shake for a long time,” CNN meteorologist Chad Myers said.

That could mean many more building collapses.

“The buildings that were damaged in the original shock have now been redamaged or reshaken,” he said. “And all of a sudden you have a cracked building, and it wants to fall down with the second shake.”

Huge impact

An estimated 750,000 people felt “violent to severe shaking,” Myers said.

“The strongest shaking was right where the most people live” in the area, he said.

While the magnitude might not seem extreme, the shallow depth of the quake — just 10 kilometers (6.2 miles) — is significant.

“When you have a shallow earthquake, such as this one is, you have the potential for more damage because the shaking is close to the surface,” John Bellini of the U.S. Geological Survey said.

In addition to destroying 19 houses, the quake hurled items off store shelves and littered streets with rubble.

But there’s one bit of good news: The quake was centered mostly under land, not an ocean, meaning it did not spawn a major tsunami.

A high-risk area

Japan, which sits along the so-called Ring of Fire, is no stranger to earthquakes.

The largest recorded quake to hit Japan came on March 11, 2011, when a magnitude-9.0 quake centered 231 miles (372 kilometers) northeast of Tokyo devastated the country.

That quake triggered a massive tsunami that swallowed entire communities in eastern Japan. It also caused catastrophic meltdowns at the Fukushima Daiichi nuclear power plant.

In all, the disaster killed about 22,000 people — almost 20,000 from the initial quake and tsunami, and the rest from health conditions related to the disaster.

Jie said Thursday’s quake gave him a new appreciation for life.

“This experience has helped me to treasure my family members and relatives even more, and not take what I have and the people who support me for granted.”

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