Things seem to have changed a little in Spain since the last time, when the biggest issue was an ash cloud emanating from Iceland!
I detected some jitters from the vendors etc. on Thursday/Friday when the police were doing the rounds of the site, there were a couple of things that I am aware of but not at liberty to discuss that happened over the weekend, I don't think the MS knew of, or expected what has happened today at the airport.
It would appear that, from a bit of internet research, players should have possibly had some form of temporary permit authorised by the local municipality in order to play over the weekend. This may have been addressed by a blanket permit granted to the MS as an an event. Obviously, the travel issue is a separate one. As the law seems to have changed in December then this weekend would have been very much a test of it.
From what I have seem, teams that decided to take early flights got some of their bags scanned and detected, bringing the issue to light. As far as I know, nobody has had a gun confiscated or destroyed, they have just been delayed by the customs/security process.