A powerful earthquake struck off southwestern Taiwan on Tuesday, triggering a tsunami warning on the second anniversary of the waves that killed more than 200,000 in southern Asia. Two hours later, seismologists lifted the warning, saying the threat of destructive waves had passed. Taiwanese media reported one person was killed and three injured in the southern city of Pingtung when their four-story home collapsed. Three other members of the family were trapped in the rubble and firefighters were working to free them, the reports said. One member of the family - an 89-year old man - escaped from the building unharmed. Initial reports said all the people in the collapsed building had been freed, but these turned out to be unfounded.