mainly on its Southwest Pacific, Southeast Asia, North Asia and Europe routes - were affected by the runway closure.

The delays in arrivals and departures were between 8 minutes and 33 minutes, SIA added.



"Passengers who needed to make flight connections were assisted accordingly," a spokesperson for the airline said.

"A multi-agency team including the Civil Aviation Authority of Singapore, Changi Airport Group, Singapore Armed Forces and the Singapore Police Force was activated for the search and locate operations," it said.

Investigations are ongoing.

Unauthorised drone flying has caused airport disruptions around the world.

In December last year, London's Gatwick airport was crippled for three days in the run-up to Christmas, causing around 1,000 flights to be cancelled or diverted and wrecking the travel plans of about 150,000 passengers.

WATCH: Lam Pin Min on vulnerabilityThis invention relates generally to the field of harvesting combines and, in particular, to an improved apparatus for feeding grain to the clean grain elevator.
Combines are used to harvest agricultural crops such as corn, soybeans, wheat and other grain crops. As the combine is driven through the crops, the combine cuts the crop, separates the desired crop from the undesired waste, stores the crop, and discards the waste.
In a typical combine, a head is mounted to the front of the combine to gather the crop and feed the crop into the combine for processing. As the combine is driven through the field, the crop material is collected by the head and deposited into a feeder housing. The crop material is then transported upwardly and into the combine by