> It was not made clear how they obtained the information, although a friend of Aditya's said the information - including the photo - could have been picked up from Gatwick Airport WiFi servers that one of the friends in the Snapchat group was using.
"Picked up from ... wifi servers" means either comms are unencrypted or there is a successful MITM presence there.
Also likely is that Snapchat just raised the alarm.