TOKYO, July 30, (AP): One of the strongest earthquakes ever recorded struck Russia’s Far East early Wednesday, sending tsunami waves into Japan and Hawaii and across the Pacific. No substantial damage has been reported so far, but authorities warned people away from shorelines and said the risk could last more than a day. Ports on the Kamchatka Peninsula in Russia near the 8.8 magnitude quake’s epicenter flooded as residents fled inland, and frothy, white waves washed up to the shore in northern Japan.

Cars jammed streets and highways in Hawaii’s capital, with standstill traffic even in areas away from the shoreline. People went to evacuation centers in affected areas of Japan, with memories fresh of the 2011 earthquake and tsunami that caused reactor meltdowns at a nuclear power plant. No abnormalities in operations at Japan's nuclear plants were reported Wednesday. Russian authorities said several people were injured without giving a figure. In Japan, at least one person was injured.

A tsunami height of 3-4 meters (10 to 13 feet) was recorded in Kamchatka, 60 centimeters (2 feet) on Japan's northern island of Hokkaido, and up to 1.4 feet (under 30 centimeters) above tide levels were observed in Alaska's Aleutian Islands. The impact of the tsunami could last for hours or perhaps more than a day, said Dave Snider, tsunami warning coordinator with the National Tsunami Warning Center in Alaska "A tsunami is not just one wave,” he said. "It’s a series of powerful waves over a long period of time. Tsunamis cross the ocean at hundreds of miles an hour -- as fast as a jet airplane -- in deep water.

But when they get close to the shore, they slow down and start to pile up. And that’s where that inundation problem becomes a little bit more possible there.” "In this case, because of the Earth basically sending out these huge ripples of water across the ocean, they’re going to be moving back and forth for quite a while,” which is why some communities may feel effects longer, he said.

Hawaii Gov. Josh Green said data from Midway Atoll, which is between Japan and Hawaii, measured waves from peak to trough of 6 feet (1.8 meters). He said waves hitting Hawaii could be bigger or smaller and it was too early to tell how large they would be. A tsunami of that size would be akin to a 3 foot (90 centimeter) wave riding on top of surf, he said.

"This is a longitudinal wave with great force driving through the shoreline and into land,” he said at a news conference. Green said Black Hawk helicopters have been activated and high-water vehicles were ready to go in case authorities need to rescue people. "But please do not put yourself in harm’s way,” he said.