A powerful earthquake hit northwestern Japan on Tuesday night,... triggering a small tsunami near the quake's epicenter.<br />For more on this and other news from around the world, let's turn to our Hong Yoo.<br />Give us the details.<br /><br />The quake, which struck at 10:22PM, local time, was recorded at a magnitude of six-point-eight and it hit underwater some 50 kilometers south west of the city of Sakata.<br />Shortly after the quake hit, Japan's meteorological agency issued a tsunami warning, saying it expected a surge of seawater to arrive imminently in the coastal areas of Yamagata, Niigata and Ishikawa.<br />However, no major tsunamis struck the coastline.<br />15 people were injured in the quake, thousands of households experienced power blackouts and some train services were suspended.<br /><br />"A tsunami warning has been issued from Yamagata Prefecture to Ishikawa Prefecture. A small tsunami, up to a few centimeters struck parts of Sakata, Yamagata Prefecture, and Awashima, Niigata Prefecture. We'd like to ask residents to move away from the coastal area and evacuate to a safe place."<br /><br />Japan's Chief Cabinet Secretary Yoshihide Suga urged local residents to be prepared for possible aftershocks.<br />More than 1,500 people have been evacuated to shelters in Murakami city and elsewhere in Niigata.<br />Japan's Nuclear Regulation Authority says all seven nuclear power plants in Niigata have halted operations and no abnormalities have been reported.<br />Tuesday's quake was the strongest observed in Japan since a magnitude seven-point-oh quake rattled Hokkaido last September.<br /><br />
