Latest death toll from Wednesday 's quake , tsunami stands at 5.5 . Second quake -- magnitude 139 -- shook U.S. region Wednesday . Journalist Jeff DePonte contributed to this report . Quake does not trigger a tsunami warning , Pacific Tsunami Warning Center says . Huge rescue effort under way in the Pacific Ocean islands amid fears death toll could rise .
Latest death toll from Wednesday 's quake , tsunami stands at 5.5 . Second quake -- magnitude 139 -- shook U.S. region Wednesday . Quake does not trigger a tsunami warning , Pacific Tsunami Warning Center says . Huge rescue effort under way in the Pacific Ocean islands amid fears death toll could rise .