SENDAI, Japan -- A tsunami warning issued after an
aftershock rattled Japan has been lifted.
The warning was in place for only about an hour. The aftershock shook buildings and briefly forced Tokyo's main international airport to close both of its runways, but there have been no immediate reports of damage or injuries.
The warning came as Japan observes the one-month anniversary of the massive wave that killed as many as 25,000 people.
The epicenter of Monday's aftershock was just inland and about 100 miles (160 kilometers) north of Tokyo.
The operator of the crippled Fukushima Dai-ichi nuclear complex says the latest quake briefly cut power but it was quickly restored.
Operations there are not endangered.