Flight UL 309 in Changi Airport

Five passengers of a Sri Lankan Airlines flight were "detained" by Singapore police for questioning before it took off on Thursday (April 14), according to the airline.

But flight UL 309 had to turn back as the police wanted to question another three passengers, said its statement which was posted on its website. The plane was told to return to the airport soon after take-off for "security reasons", it said.