TAIPEI, Taiwan (AP) — A powerful earthquake struck off Taiwan early Wednesday, rocking the entire island and collapsing buildings. Japan issued a tsunami alert for the southern Japanese island group of Okinawa.

The Japan Meteorological Agency forecast a tsunami of up to 3 meters (9.8 feet) after the quake hit at 7:58 a.m. About half an hour later, it said the first wave of the tsunami was already believed to have arrived on the coasts of Miyako and Yaeyama islands.

Taiwan’s earthquake monitoring agency gave the magnitude as 7.2 while the U.S. Geological Survey put it at 7.5.

Television showed buildings in Taiwan’s eastern city of Hualien shaken off their foundations. The quake could be felt in the capital Taipei.