Tsunami warning issued after quake

? Thousands of people living along northern Japan’s Pacific coast fled to higher ground Wednesday after a powerful undersea earthquake prompted tsunami warnings as far away as Alaska.

The 8.1-magnitude quake struck an area claimed by both Russia and Japan, but the waves did not swell higher than 23 inches. There were no immediate reports of casualties or damage.

Japan’s meteorological agency withdrew its tsunami warning after about three hours. Tsunami warnings posted for Russia and coastal areas of Alaska also were canceled, as were tsunami watches for Hawaii, the Philippines, Taiwan, Indonesia and several Pacific islands.

Small tsunami, some measuring several feet high, crashed into Hawaii, slightly injuring one swimmer, and ocean surges buffeted a northern California harbor, damaging docks.