One of the strongest earthquakes to hit the South Pacific in modern history triggered tsunami warnings across the ocean and forced thousands of people in New Zealand to evacuate coastal areas Friday. The magnitude 8.1 quake in the Kermadec Islands region about 1,000 kilometers (620 miles) from New Zealand's two main islands was the largest in a series of temblors over several hours, including two earlier quakes that registered magnitude 7.4 and magnitude 7.3. The tsunami threat caused traffic ja