U.S. Navy spy plane collides with Chinese aircraft.(Knight Ridder Newspapers)

BEIJING _ A U.S. Navy spy plane with 24 crew members aboard collided Sunday over the South China Sea with a Chinese jetfighter dispatched to intercept it. The Chinese plane crashed and the American aircraft made an emergency landing on a Chinese island.

The fate of the Chinese pilot was unknown. The American crew was reported to be uninjured and safe at a military airfield on the Chinese island of Hainan.

The Bush administration said diplomatic efforts were underway to gain release of the crew and their EP-3E Aries II aircraft. It is a four-engine turbo-prop loaded with highly classified equipment capable of intercepting radar, radio, telephone signals and other electronic emissions.

China said the "U.S. side has total responsibility for this event," asserting that the EP-3E suddenly veered and hit one of two Chinese jetfighters scrambled to intercept the American aircraft as it neared China's airspace. It said it protested the incident to the United States and reserved the right to seek compensation.

The U.S. Pacific Command, based in Hawaii, said that its plane was on a "routine surveillance mission" in international airspace. U.S. officials said they were awaiting details on the exact cause of the collision. It occurred 60 miles south of Hainan Island, the Chinese said. If so, that was outside Chinese territory.

The incident threatened to ignite a serious diplomatic crisis at a time of rising uncertainty in Sino-U.S. ties, especially if Chinese military officers try to enter and inspect the aircraft.

"This has got to create problems for the relationship," said Warren I. Cohen, a professor of U.S.-Chinese relations at the University of Maryland-Baltimore County.