Two people were killed when an Asiana Airlines cargo plane crashed on Thursday off South Korea's southern island of Jeju after reporting mechanical problems, officials said.
Debris from the aircraft, which had taken off from Incheon at 3.05 am headed for Pudong in east China, was found by a coast guard patrol boat just over 100 kilometres (60 miles) west of the island, a Jeju coastguard spokesman said.
Four coastguard boats and a helicopter are searching the area, he told AFP.
The Boeing 744 plane carrying a pilot and co-pilot called Jeju airport at 4.11 am to request an emergency landing because of mechanical problems, an Asiana spokesman said.
The 744 is also known as the 747-400.
Asiana is the country's second and smaller flag carrier. It largely operates short-haul routes into Asia.