DALLAS (BLOOMBERG) - London's Gatwick airport temporarily halted flight operations on Wednesday (Dec 19) night after reports of two drones flying over the airfield.

More than two dozen arriving planes have been diverted, according to flight-tracking service Flightradar24. It wasn't immediately clear how many flights were affected in total, said Mr Mark Lever, a Gatwick spokesman.

"We apologise to any affected passengers for this inconvenience, but the safety of our passengers and staff is our foremost priority," the airport said in a statement.

In a separate incident last week that raised alarms about the risk to jetliners from unmanned aerial vehicles, Grupo Aeromexico SAB is investigating whether a drone slammed into a Boeing 737 aircraft as the plane approached its destination in Tijuana, Mexico. The jet sustained damage to its nose but landed safely.

While most nations prohibit drones from flying in pathways reserved for airliners, the millions of small consumer devices that have been purchased around the world can't be tracked on radar, making it difficult for the authorities to enforce the rules. In addition, many users don't know the restrictions or don't follow them.