TAIPEI, Taiwan— A 7.4-magnitude earthquake, followed by several strong aftershocks, struck off the east coast of Taiwan on Wednesday morning, killing seven people and injuring at least 736, according to Taiwan’s fire department. The earthquake hit about 15 miles south of Hualien county just before 8 a.m. local time, damaging buildings and causing landslides. The U.S. Geological Survey measured its magnitude at 7.4. It was the largest earthquake to hit Taiwan in 25 years and was also felt in parts of China.