Flight recorders from the passenger jet that crashed in South Korea last month, killing more than 170 people, stopped working minutes before the plane belly-landed and exploded on the runway, investigators said Saturday.

The black boxes of a Boeing jetliner that crashed in South Korea last month stopped recording about four minutes before the accident, South Korean officials said Saturday, possibly complicating investigations into the cause of the disaster that killed 179 people.

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