The helicopter crash that last year killed Kenya's Internal Security Minister George Saitoti and five other people was most likely caused by pilot error during bad weather conditions, a commission investigating the accident said Thursday.
There were no survivors in the June 10 accident that occurred in Ngong, a town on the outskirts of Nairobi. The police helicopter went down soon after take-off from Nairobi's Wilson Airport.
"The probable cause of the accident was a loss of aircraft control in poor visibility," commission president Kalpana Rawal told reporters, reading out a summary of the report.
The commission was set up shortly after the accident, with President Mwai Kibaki vowing to make the findings public.
Commission member Peter Maranga said a "pilot error... may have played a key role in this accident. It is possible the two pilots did not have enough experience to fly in bad weather."
The panel also said it had found "serious deficiencies in the areas of training, safety management and airworthiness" in the Kenyan police's air squadron and said maintenance of the aircraft had been carried out by an "unauthorised" mechanic.
The commission also said it had discovered a large "error" on behalf of Eurocopter -- the manufacturer of the crashed aircraft -- as a part of the aircraft's system had been replaced with a "prototype" piece a few days before the helicopter was delivered to the Kenyan police.
The commission did not say if the part played any role in the accident.
The aircraft, an AS350 B3e, was built in 2011 and delivered later that year.
Eurocopter, a 100-percent subsidiary of European aeronautics and defence group EADS, did not immediately comment on the findings.
In its inquiry, the commission recommended a complete overhaul of the Kenya Civil Aviation Authority.
Aside from Saitoti, the minister's assistant, two bodyguards and the two pilots died in the crash.