WASHINGTON (AP) — A fighter jet and a helicopter based off the aircraft carrier USS Nimitz both crashed into the South China Sea within 30 minutes of each other, the Navy’s Pacific Fleet said.

The three crew members of the MH-60R Sea Hawk helicopter were rescued on Sunday afternoon, and the two aviators in the F/A-18F Super Hornet fighter jet ejected and were recovered safely, and all five “are safe and in stable condition,” the fleet said in a statement.

The causes of the two crashes were under investigation, the statement said.

President Donald Trump, speaking to reporters aboard Air Force One en route to Tokyo on Monday, said the incidents could have been caused by “bad fuel.” He ruled out foul play and said there was “nothing to hide.”