Passengers on board the Boeing 777-300ER flight from Melbourne, Australia, to the United Arab Emirates capital of Abu Dhabi said Tuesday's fires sent smoke into the cabin and appeared to have been deliberately set.
Smoke was detected in two toilets after takeoff from Melbourne on Monday, prompting a precautionary diversion to Jakarta, Indonesia, and again in a toilet as the plane made its way to its destination of Abu Dhabi, according to the government-backed airline.
None of the 254 passengers and crew was removed from the flight in Indonesia. Several passengers said that decision was unnerving given the fears that the fires were started by someone on board.
Twelve people were detained upon arrival in Abu Dhabi as authorities investigated the case. A young woman who had attracted the suspicions of some passengers was among those initially detained, witnesses said.
"The real story is: Who was the idiot woman trying to burn a plane down, and why," passenger Mark Sinclair, 45, said by email. "She should be in jail for a very long time."
The 12 passengers held for additional questioning were offered hotel accommodation but opted to stay together and were kept in the airline's first-class lounge, according to Etihad. It said consular officials from Australia, the United Kingdom and Ireland visited them.
By Thursday morning, all had been allowed to continue on their journeys.
"In the absence of any conclusive incriminating evidence, no arrests have been made at this time," the airline said in an emailed statement.
Etihad described the investigation as ongoing, and said it is co-operating with authorities.
"We have a zero-tolerance policy in respect to people who threaten the safety and security of passengers and crew or our aircraft," the airline said.
Officials at the Abu Dhabi police department, which is leading the probe, could not be reached for comment.
The UAE's aviation regulator, the General Civil Aviation Authority, said it is involved in the investigation and confirmed that no arrests have been made.
Australia's Civil Aviation Safety Authority said Thursday that responsibility for any safety investigation resides with the regulator in the UAE. Any security issues would be investigated by national security agencies, CASA spokesman Peter Gibson said.
CASA expects to be notified of the results of any safety investigation because Etihad has approval to fly into Australia.
"If it involves any safety issues, we would expect to receive some information from Etihad in due course," Gibson said.
Etihad is the UAE's national carrier and is based in Abu Dhabi. It and Gulf competitors Emirates and Qatar Airways have been rapidly expanding their operations in recent years, turning their desert bases into major intercontinental transit hubs.
Its Australian destinations are Brisbane, Melbourne and Sydney. It also has a minority stake in Virgin Australia.
Associated Press writer Rod McGuirk in Canberra, Australia, contributed to this report.
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