TOKYO - A tsunami of up to 40 centimeters was observed on early Thursday morning at a port of Iwate Prefecture, which lies on the Pacific coast of northeastern Japan, after a powerful 8.2-magnitude earthquake in Chile, local media reported.

The Japan Meteorological Agency has issued a tsunami alert for Pacific coastal areas of Hokkaido and the Tohoku region, some parts of the Kanto region and the Izu and Ogasawara islands.

According to Japan's Kyodo News, Iwate's Kuji port also observed a tidal wave of about 20cm at 6:52 am local time, bigger tsunamis were monitored later.

A mighty 8.2-magnitude earthquake struck off the coast of northern Chile late Tuesday, triggering small landslides, cutting power and generating a tsunami. It has left six people dead, according to Chile officials.