A new earthquake in Japan is not expected to trigger an ocean wide tsunami. That's according to the Pacific Tsunami Warning Center. Japan was just rattled by a strong 7.4 magnitude aftershock and tsunami warning nearly a month after a devastating earthquake and tsunami flattened the northeastern coast. The Japan Meteorological Agency issued a tsunami warning for a wave of up to 6 feet. The warning was issued for a coastal area already torn apart by last month's tsunami, which is believed to have killed some 25,000 people and has sparked an ongoing crisis at a nuclear power plant.