“Black boxes” from crashed South Korean plane stopped recording about four minutes before disaster, officials say

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

Officials probing the country’s deadliest aviation accident in almost three decades had hoped information from the so-called black boxes would shed light on why Jeju Air flight 7C 2216 from Bangkok belly-landed at Muan International Airport on December 29, erupting into a fireball.

The disaster killed 179 passengers and crew members. Two people survived.

But South Korea’s transport ministry said Saturday that both the cockpit voice recorder (CVR) and flight data recorder (FDR) from the Boeing 737-800 had stopped working about four minutes before the crash.

In a statement, the ministry said it was unclear why the devices stopped recording, adding that it will work to determine the cause.

“CVR and FDR data are important data for accident investigations, but accident investigations are conducted through investigation and analysis of various data, so we plan to do our best to accurately identify the cause of the accident,” the ministry said.

The cockpit voice data recorder was first analyzed locally and later sent to the United States for cross-checking, the ministry said.

The flight data recorder was sent to the National Transportation Safety Board in the US for analysis, after the South Korean authorities concluded they were not capable of extracting data from the device due to external damage.

CNN has contacted the NTSB for comment.

For more CNN news and newsletters create an account at CNN.com