LONDON — More than a week after somebody (or somebodies) with a drone (or drones) shut down a major airport and ruined the travel plans of tens of thousands of people, the British police had little to offer on Thursday except warnings about how little they had to offer.

“You won’t find a police service in the world, I think, who is sitting complacently thinking, ‘Well, we could always deal with a drone,’ ” Cressida Dick, the commissioner of the Metropolitan Police Service, told BBC 4 radio. “You won’t find it. It’s a difficult challenge.”

The shutdown of Gatwick Airport for almost a day and a half last week showed how easily the sophisticated global aviation network can be crippled by someone with even limited resources, how vulnerable the system is to mischief — or worse — and how hard it can be to find the culprits. The police have no one in custody in the case, they have suggested that they are still unsure of a motive and they are not certain how many drones were involved.

Some members of Parliament called this week for the Metropolitan Police to take over the investigation from the Sussex Police. The Metropolitan force, which primarily polices London, handles antiterrorism cases nationwide, but officials have not concluded that the Gatwick episode was an act of terrorism — nor that it was not.