Chile’s air force has said it has lost radio contact with a transport plane carrying 38 people on a flight to the country’s base in Antarctica.
It said the military had declared an alert and activated search and rescue teams after communications went down on Monday evening.
The C-130 Hercules was carrying 17 crew and 21 passengers, including three civilians. They were being flown in to check on a floating fuel supply line and other equipment at the Chilean base.
President Sebastián Piñera tweeted that he was with his defence and interior ministers at the air force headquarters monitoring developments.
The plane took off at 4.55pm from the southern city of Punta Arenas, which is more than 3,000km (1,860 miles) from the capital of Santiago. Contact was lost at 6.13pm, the statement said.
The air force said late on Monday that the weather good at the time contact was lost.
General Eduardo Mosqueira of the Fourth Air Brigade told local media a search was underway and a ship was in the area where the plane should have been when contact was lost.
Mosqueira said the aircraft would have been about halfway to the Antarctic base at the time communications went down. No emergency signals had been activated, he said.
He said the plane, whose pilot had extensive experience, had been scheduled to return on Monday night.