Would you do the same?

I live in a block of flats, we're all council tenants. Every single day someone leaves the main door wide open for anyone to wonder in. It can be at all hours, I went out the other day at 5am and it was wide open! I've come home at 2am and it's wide open. All households bar one have children. My children's father came over the other day at around 6pm and he seen some random pissed up man try and open it, realised it was actually shut walked off. That's absolutely terrifying..me and my 2 neighbours all have kids under 2. We know it's not us 3. Would you complain to the council and say something needs to be done as I don't feel very safe? I think I know who's doing it but without proof can't really say