TOKYO, Japan (CNN) -- Three people were killed and at least 84 were injured Saturday morning when a magnitude 7.0 earthquake struck northeastern Japan, Japanese officials said.

The quake struck at about 8:43 a.m. north of Sendai, Japan.

Another five people were missing, national police said.

Officials said the earthquake led to the buckling of highways and caused some bridges to collapse. Bullet trains were also stopped in the affected areas.

Two nuclear power plants in the region were not affected, officials said.

Cabinet Secretary Nobutaka Machimura said one man was killed when he was buried in a landslide in Fukushima Prefecture and the other was struck by a truck as he rushed out of his house in Iwate Prefecture. Officials have not yet released details of the third death.

Prime Minister Yasuo Fukuda sent priority orders for rescue operations, Machimura said.

The quake, which struck at about 8:43 a.m. (11:43 p.m. GMT Friday), was centered 100 km (60 miles) north of Sendai in southern Iwate prefecture. The Japanese Meteorological Agency said several strong aftershocks followed the initial quake.

The Iwate government office said it had received reports that eight children and a teacher were injured by breaking windows at a preschool and that the earthquake produced landslides in some areas.

The Miyagi fire department said there had been some injuries caused by falling furniture, and some bus passengers were injured when the vehicle bounced on a bridge. Two houses collapsed, the fire department said.

East Japan Railway suspended Shinkansen bullet trains in the Tohoku region, and many other train lines in the region suspended operation as well. Expressways in Miyagi were also closed.

Tokyo Electric Power Co. said that operations at nuclear power plants in Fukushima prefecture were not affected, Kyodo said.

There were no tsunami warnings issued after the quake.

Local governments, fire departments and police were working to gather damage reports.

CNN's Junko Ogura and Yoko Wakatsuki contributed to this report.

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