TALCA, Chile - (AP) - One of the largest earthquakes ever recordedtore apart houses, bridges and highways in central Chile onSaturday and sent a tsunami racing halfway around the world.Chileans near the epicenter were tossed about as if shaken by agiant, and the head of the emergency agency said authoritiesbelieved at least 300 people were dead.

The magnitude-8.8 quake was felt as far away as Sao Paulo inBrazil - 1,800 miles (2,900 kilometers) to the east. The fullextent of damage remained unclear as dozens of aftershocks - onenearly as powerful as Haiti's devastating Jan. 12 earthquake -shuddered across the disaster-prone Andean nation.

President Michelle Bachelet declared a "state of catastrophe"in central Chile but said the government had not asked forassistance from other countries. If it does, President Barack Obamasaid, the United States "will be there." Around the world,leaders echoed his sentiment.

At least 214 people were killed and 15 were missing as ofSaturday evening, Bachelet said in a national address ontelevision. While that remained the official estimate, CarmenFernandez, head of the National Emergency Agency, said later: "Wethink the real figure tops 300. And we believe this will continueto grow."

Bachelet also said 1.5 million people had been affected by thequake, and officials in her administration said 500,000 homes wereseverely damaged.

Also near the epicenter was Concepcion, one of the country'slargest cities, where a 15-story building collapsed, leaving a fewfloors intact.

In the capital of Santiago, 200 miles (325 kilometers) to thenortheast, the national Fine Arts Museum was badly damaged and anapartment building's two-story parking lot pancaked, smashing about50 cars whose alarms rang incessantly.

Santiago's airport was closed, with smashed windows, partiallycollapsed ceilings and destroyed pedestrian walkways in thepassenger terminals. The capital's subway was shut as well, andtransportation was further limited because hundreds of buses werestuck behind a damaged bridge.

The jolt set off a tsunami that swamped San Juan Bautistavillage on Robinson Crusoe Island off Chile, killing at least fivepeople and leaving 11 missing, said Guillermo de la Masa, head ofthe government emergency bureau for the Valparaiso region. He saidthe huge waves also damaged several government buildings on theisland.

The surge of water raced across the Pacific, setting off alarmsirens in Hawaii, Polynesia and Tonga and prompting warnings acrossall 53 nations ringing the vast ocean.