The search for an Asiana Boeing 747-400F that crashed into the sea more than a month ago off South Korea is continuing.

The beacon of the aircraft's cockpit data recorder and voice recorder are likely to have been damaged in the 28 July incident, said a spokesman for the airline.

"Hence, it is very difficult for us to pinpoint the location of the aircraft," he added.

The aircraft, with the registration HL-7604, went missing off Jeju Island while en-route from Seoul to Shanghai's Pudong International airport.

The crew had reported "control problems" at an altitude of 7,600ft and that there was a fire in the hold, said the South Korean Ministry of Land, Transport and Maritime Affairs (MLTMA) shortly after the crash. It had diverted to Jeju International airport when it crashed, it added.

Asiana contracted Japan's Nippon Salvage Company on 2 August to aid in the search efforts. The search team includes officials from the ministry and Asiana. The US National Transportation Safety Board (NTSB) has also dispatched a team to aid the investigation. NTSB has designated safety investigator John Lovell as the US accredited representative in the investigation, and he will be assisted by NTSB staff and advisors from the US FAA and Boeing.

The ministry said on 29 July that while the "fire probably caused the crash", its exact role in the incident has not yet been determined.

The aircraft was carrying cargo that included lithium batteries, paint and other potentially dangerous materials.

While there is no immediate evidence that the cargo contributed to the accident, lithium batteries are considered a potentially hazardous because they pose the risk of in-flight fire.

Source: Air Transport Intelligence news