A 6.9-magnitude earthquake deep under the ocean floor struck offshore Okinawa, Japan, just before noon Tuesday, the U.S. Geological Survey reported.There were no immediate reports of injuries or damage.CNN reported no tsunami alerts were issued.The USGS said the quake, 130 miles under the ocean floor, struck at 11:59 a.m. local time 133 miles northwest of Naha, Okinawa, 310 miles east-northeast of Taipei, Taiwan, and 710 miles south of Seoul.CNN quoted the Pacific Tsunami Warning Center the quake did not set of a tsunami.Okinawa is more than 1,000 miles from Fukushima in northeastern Japan.The region was devastated by a 9-magnitude earthquake and a tsunami on March 11. A nuclear crisis set off by that quake at the Fukushima Daiichi nuclear plant is yet to be fully contained.