A tsunami warning was issued for New Zealand and Tonga after a magnitude 7.7 earthquake struck off the coast of the Kermadec Islands at 7:03 a.m. local time Thursday (3:03 p.m. ET Wednesday.)

The U.S. Geological Survey (USGS) initially reported the quake had a magnitude of 7.9, but that was later downgraded to a magnitude of 7.7. The depth was revised from 48 km to 1 km.

Hawaii and the continental U.S. were not placed under a tsunami alert.