Officials say the black boxes of a Boeing jetliner that crashed in South Korea last month stopped recording about four minutes before the accident.

The last four minutes of data before the disaster which killed 179 people are missing, transport authorities say.

The two black boxes on the Boeing jet involved in the worst aviation disaster on South Korean soil stopped recording about four minutes before the accident, the transport ministry said on Saturday. South Korean investigators previously said the flight data and cockpit voice recorders were key to finding out the cause of last month's crash that killed 179 people.