Sri Lanka, June 25 -- A powerful earthquake struck off Japan's northern coast on Thursday, but the country's meteorological agency said there was no danger of a tsunami.

The quake had a magnitude of 7.2 and occurred off the eastern coast of Iwate, upgraded from an initial reading of 6.9, the Japan Meteorological Agency said. The quake had a depth of about 50 kilometers (30 miles), it said. JMA The U.S. Geological Survey also reported a magnitude of 6.9.

The rattling occurred in an area where strong earthquakes have repeatedly been reported in recent months, including one that triggered a weeklong mega-quake caution advisory in December.

The quake, which struck Japan's northeastern region during Thursday morning's rush hour, also mildly...