A Taiwan aircraft captain clarified that the cause of the emergency landing is to avoid a midair collision with another plane, not because of the air turbulence.

Chen Shih-han, the captain of the Far Eastern Air Transport (FAT) flight EF 306, made the above statement after his crew returned to Taiwan on November 17, Taiwan media reported.

The FAT Boeing 757 aircraft, with 129 passengers and eight crew aboard, was forced to make an emergency landing on South Korea's southern tourist resort Cheju island in the morning of November 16, injuring 25 aboard.

Chen said everything is smooth after the aircraft took off from Taipei, but when it was over the Cheju island of South Korea, the Traffic Collision Avoidance System (TCAS) of the flight made an alarm signal, indicating another plane was near, which prompted him to abruptly change course to avoid collision.

Chen didn't receive the South Korean airport control tower's alert until the TCAS alarm of his flight went off. The tower's late alert showed there was a Thai Airways aircraft in the same area.

After the unexpected descent in line with the required procedures, Chen asked the control tower what had happened but received no answers, he said.

Chen apologized to all passengers, saying he made the descent decision completely out of the avoidance of collision, but not out of air turbulence.

Three of the 25 injured passengers were sent to the Cheju local hospitals to receive treatment. The rest have already been recovered from slight injuries.

Two FAT crew members are helping the authority to investigate the incident, according to the media.