TOKYO -- Officials have lifted a tsunami warning for the coast of Japan, 90 minutes after a major earthquake struck offshore.
The quake off northeastern Japan had prompted a warning for a wave up to 6 feet in the same coastal area devastated by last month's tsunami.
The aftershock shook buildings and knocked out power, but no major damage has been reported.
Officials evacuated two workers at the nuclear power plant damaged in last month's quake and tsunami, and seven at a sister plant to the south. But they say there's no sign of any new problems.
Thursday's aftershock was centered at about the same location and depth as last month's 9.0 quake. Japanese officials said today's quake was a 7.4, while the U.S. Geological Survey in Golden, Colo., measured it at 7.1.