First of all, there should be security staff padding down people in the entrance of the club to prevent this kind of shit. This is a thing I noticed in Spain as well, you can walk into any club, festival with whatever you got, knifes, guns, and security don't do shit... imagine some terrorist walks into a big festival like Monegros, 40,000 people and decides to blow himself up?

They should have enforced these rules, especially after what happened in Madrid in 2004.