Per other news reports, kinetic kills were ruled out because of unacceptable risk of bullets/shells hitting something they shouldn't — the whole of South-East England is populated at a density that Americans would call suburbia. (All of England is only one and a half times as large as Greater Los Angeles County: lots of small towns, villages, and homes in the vicinity of Gatwick.)
I'm surprised they don't have specialist anti-drone transmitters, but as Police spending in England and Wales has been cut by over 30% since 2010, maybe it wasn't seen as a priority.
Tracking down the operators should be possible, but this looks like a well-planned attempt to shut down the airport: whoever is behind it probably planned to move around in order to evade the Airport Police.
I'm surprised they don't have specialist anti-drone transmitters, but as Police spending in England and Wales has been cut by over 30% since 2010, maybe it wasn't seen as a priority.
Tracking down the operators should be possible, but this looks like a well-planned attempt to shut down the airport: whoever is behind it probably planned to move around in order to evade the Airport Police.