Two strong back-to-back earthquakes struck early Thursday off the northeastern coast of Japan, prompting a short tsunami warning.

A 6.8 quake was centered about 136 kilometers southeast of Hachinohe.  It was immediately followed by a 6.7 magnitude quake. There are no immediate reports of damage or injuries.

Officials issued a tsunami warning, but canceled it about one hour later.

Hachinohe is north of the epicenter of the devastating March 8.9 magnitude quake and tsunami.

Some information for this report was provided by AFP.