The Air Accidents Investigation Branch (AAIB) explained their findings into the helicopter's loss of control which resulted in the death of five people.
Britain's air accident investigator said Thursday that the helicopter crash that killed the Thai owner of Leicester City football club was caused by the disconnection of a pedal operating the tail rotor.
Leicester air crash findings
The Air Accidents Investigation Branch (AAIB) said the helicopter's loss of control appeared to result from "the tail rotor actuator control shaft becoming disconnected from the actuator lever mechanism."
The AAIB said air safety experts were urgently investigating "the initiating cause and exact sequence of the failure" of the tail rotor in the Agusta AW169 helicopter.
The branch said it would examine the possible contribution of damage to a bearing in the system and "identify any other factors that may have contributed to the loss of tail rotor control."
The aircraft crashed outside Leicester City's King Power Stadium on October 27 following a football match in the English Premier League.
The club's 60-year-old owner, Vichai Srivaddhanaprabha, the fifth-richest person in Thailand, was among the five people who died in the crash.
Vichai, who made his fortune from an airport duty-free monopoly, took ownership of Leicester in 2010, pouring money into the club and becoming a popular figure in the city through his many charitable donations.
His popularity peaked when the team won the Premier League for the first time in 2016.