PANAMA CITY, Panama (AP) _ A twin-engine plane carrying 22 people crashed Wednesday minutes after takeoff from Contadora island when birds were sucked into its right engine, Aeroperlas airline said. It said 20 people were missing and two were rescued.

Passenger lists showed four Americans aboard the aircraft, the airline and control tower said.

U.S. planes, boats and divers joined Panamanian rescue workers in the search for survivors of the Twin Otter plane in 120-foot-deep Pacific waters three miles south of the resort, the U.S. Southern Command said.

The search was suspended Wednesday night and will resume Thursday morning, said Panama's director of civil aviation, Jaime Fabrega.

The Americans were listed as Anita Heck, Karl Heck, Lisa Larglow and Richard Poux, according to Panamanian civil aviation sources. No hometowns and ages were available, and late Wednesday the State Department in Washington said it had no details on the plane crash or the Americans on board.

Asked if other survivors had been located, Fabrega said, ''For now, no.''

He told reporters, ''Since we haven't reached the plane, it would be foolish to say anything more.''

A statement by the airline blamed the crash on the failure of the right engine after a group of birds flew into it at takeoff. Aviation experts say that in such incidents, the impact of the birds causes the engine's turbines to stop, forcing the plane to stall.

The statement added that those rescued and taken to Panama City were ''Frederick Pirot Jr., 14, and Mrs. Ana Jury.'' The passenger list shows two others with the name of Pirot - presumably related to him.

Mrs. Jury, of Switzerland, suffered a broken vertebra, and Pirot, of France, suffered a broken arm, the airline said.

The rest of the passengers and two crew members were Panamanians, the Civil Aviation office said.

The plane was en route from Contadora, about 50 miles southeast of Panama City, to the capital.

The Pacific resort island is where former Panamanian leader Omar Torrijos gave refuge for several months to the Shah of Iran, Mohammad Reza Pahlavi, after the shah's 1979 exile.

It also was the site of a 1981 meeting by four Latin foreign ministers, Mexico, Venezuela, Colombia and Panama, to negotiate the first attempts at peace in Central America.