A bus carrying the bereaved families of Jeju Air plane crash victims arrives at the crash site at Muan International Airport in South Jeolla Province, Wednesday. Yonhap

The government will inspect navigation facilities that assist in aircraft landings at all domestic airports, following mounting evidence that a concrete structure supporting a localizer — a navigation aid — may have exacerbated the severity of the impact when the ill-fated Jeju Air plane crashed at Muan International Airport, the transport ministry said Wednesday.

The investigation will focus on whether the materials used for the structure and its distance from the runway comply with domestic and international standards.

The Ministry of Land, Infrastructure and Transport said it is investigating the materials used in navigation aid facilities at all airports nationwide. The localizer, a key navigational aid, helps aircraft align with the runway during landing.

On Sunday, Jeju Air's Boeing 737-800 plane struck a concrete structure supporting the localizer, causing damage to the fuselage and sparking a fire that claimed 179 lives out of 181 passengers on board, according to the ministry.

The use of concrete for such structures dates back over 20 years, at the time of designing the Muan International Airport, it said.

During briefings on Monday and Tuesday, ministry officials initially defended the navigation facility at Muan airport, asserting it met regulatory standards. They also claimed that similar concrete structures were present at international airports, including Los Angeles International Airport (LAX) in the United States and Tenerife Airport in Spain.

However, controversy grew after it was revealed that the ministry's regulations on airport and airfield installation standards require extending a safety zone to the point where navigation safety facilities are installed.

Further doubts have emerged within the aviation industry, with satellite images suggesting that airports like LAX may not have similar concrete structures.

Ministry officials then said they plan to conduct a comprehensive review of regulations from the International Civil Aviation Organization and other major aviation authorities, including cases of airports overseas.

"We will provide a detailed explanation soon, based on a thorough review and expert consultation," an official said. "While our records indicate such structures exist, we will verify and address claims that no such concrete mounds are present at other airports."

Meanwhile, all 179 victims of the tragic plane crash have now been identified, including the last five whose identities were not confirmed until Tuesday, according to the Central Disaster and Safety Countermeasure Headquarters.

Acting President Choi Sang-mok confirmed that the identification process was completed overnight, and the remains have been returned to the victims' families. Funeral arrangements are underway with the deceased now resting at funeral halls.

Choi ordered relevant ministries to provide full support to the bereaved families. He also emphasized the importance of an objective and thorough investigation into the cause of the crash, calling for transparency in the process and its findings.

Meanwhile, the transport ministry said it will send the flight data recorder from the crashed Jeju Air plane to the U.S. for analysis. The date of the transfer will be determined after consultation with the National Transportation Safety Board (NTSB), it said.

The recorder reportedly suffered external damage and lost a connector that links its data storage unit to the power source.