A 6.7 magnitude earthquake shook northeastern Japan and caused small tsunami waves but no apparent damage Friday, days after a stronger quake in the same region.

Friday's quake occurred off the east coast of Aomori prefecture, in the north of Honshu, the main Japanese island, at a depth of about 12 miles, according to the Japan Meteorological Agency, which issued a tsunami advisory that was lifted about two hours later.

Small waves were reported in Hokkaido and Aomori prefectures, but no serious damage or injuries were reported.

The quake followed a 7.5 magnitude earthquake Monday that caused injuries, light damage and a small tsunami on Japan's Pacific coast.

No tsunami alerts were issued Friday for the West Coast of the U.S. or Hawaii.

Monday's earthquake, also off the coast of Aomori, caused at least 34 injuries and damaged roads and buildings. It also triggered a tsunami of up to 28 inches in some Pacific coast communities.

It prompted Japan on Tuesday to issue a megaquake advisory.

The government estimated that an offshore megaquake could cause a tsunami of up to 98 feet and kill nearly 200,000 people. Officials said the advisory was not a prediction, and the probability of a magnitude 8 or larger quake was only about 1%.

There was hope the advisory would serve as a wake-up call for a quake that could have the devastation of the 2011 disaster that killed nearly 20,000 people and destroyed a nuclear plant.

Monday's quake temporarily increased potential risks in the regions of Hokkaido and the Sanriku coast. That's where the Pacific Plate beneath Japan forms the two trenches — the Japan Trench and Chishima Trench — that have caused many large quakes in the past.

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