Japanese and U.S. officials say two American warplanes crashed into the Pacific Ocean off Japan's southwestern coast after a midair collision early Thursday, and search and rescue operations are underway.

The U.S. Marine Corps said Thursday an FA-18 fighter and a KC-130 tanker aircraft were involved "a mishap" off the Japanese coast early Thursday. It said in a statement that the accident is under investigation and gave no further details.

Japan's Defense Ministry said the two aircraft carrying seven crew members altogether had collided midair and crashed into the sea about 100 kilometers (60 miles) south of the Muroto cape on the Shikoku main island.

They said Japanese rescuers found one of the crew members in stable condition. Japanese officials said two crew members were on FA-18, and five others on KC-130.