Attack(?) in Nottingham Cathedral

(Update) No one was hurt: https://www.facebook.com/share/p/1U559dxpSo/

I was attending a mass at Nottingham Cathedral today (5th Jan) when a guy entered the chuch carrying a black bag. I was seated at the back right side of the church so I didn't see what he did, but people started screaming and and running towards the exits. I also tried my best to get out of the church fast so I slipped got scratches. On my way home, I saw people reporting it to the police..