Abu Dhabi: A dozen passengers were detained in Abu Dhabi by local officials after smoke was detected in cabin toilets on an Abu Dhabi-bound Etihad Airways flight, the airline said.

The passengers have not been arrested and an investigation is underway, Etihad, the UAE’s national airline, said in a statement on Wednesday.

“The aircraft was searched and released shortly after arrival at Abu Dhabi [on Tuesday] when it was confirmed it was safe to do so,” it added.

“A total of 12 passengers are still being held by Abu Dhabi security authorities. Etihad Airways is cooperating fully in this investigation.”

Passengers and crew of flight EY 461 were interviewed by UAE authorities, the airline said, after a delayed landing in Abu Dhabi on Tuesday.

It added that the flight — after taking off from Melbourne, Australia, on Monday — was diverted to Jakarta, Indonesia, “as a precautionary measure” when smoke was detected in two toilets.

The flight landed “normally” and local authorities assisted the pilot carry out “a security assessment of the situation”.

The aircraft, passengers and carry-on luggage were searched before the plane took off for Abu Dhabi, Etihad said.

The captain placed “strict controls” on passenger movement in the cabin, especially on access to toilets.

However, two hours before landing in Abu Dhabi, another toilet smoke alarm went off as cabin crew were preparing the meal service.

The smoke was “dealt with immediately by the crew,” who continued to “monitor and secure toilet access for the remainder of the flight.”

Etihad said “the events that occurred during the flight remain under investigation.”

Australian news site news.com.au quoted an unnamed passenger as claiming “an arsonist” was behind the incident. According to the report, the passenger said “there was an announcement reminding us all smoking was strictly prohibited. [Airline staff] assumed that’s what caused it.”