Days after two south London schools closed early because of the threat of gang violence outside their gates, police gun crime unit Operation Trident has launched its latest effort to stop teenagers carrying guns.
The poster is Trident's latest effort to stop youths carrying guns
"Cathy", from south London, has two sons aged 21 and 19 who are both in the same gang, sell drugs and are known to Trident officers. She knows two people who have been shot dead in the past 18 months.
She rang BBC London's Vanessa Feltz radio show to describe how the constant strain had led to her losing her job, her daughter having to move and repeated police raids on her home.
It started when my eldest son was around 14 or 15. I knew there were gangs but I didn't think my sons were associated with them.
I thought they were going to school, I thought they were doing the normal stuff kids do.
I started to find money. I was a single parent but I was working and I knew this money wasn't coming from me. I would ask them where this money had come from and they would just be secretive - and then I got scared.
I tried talking to them, I tried saying, 'If you are black be proud, you don't just have to be like this'. I tried to pump education into them, I don't know, it all fell apart.
[The gang] took over their whole life. They completely changed. Completely.
It escalates from petty silly things, the street fights... I just don't want to say too much.
That is their lives, that's the way they think, that's their mentality. That's just the way they live.
I have a 24-year-old daughter - she's had to move. The police moved her because of the situation with her brothers. They said: 'You have to move, we have had intelligence that your brothers are doing...', well, I can't really say.
It just goes on and on and on. I lost my job 18 months ago because of the constant house raids.
Once you are targeted by Trident, it doesn't stop. They don't say, 'OK, we did find a firearm but your prints are not on it, so bye bye'. It just goes on constantly - it doesn't stop.
I prayed, I have talked to them. I have begged them. I have worked hours and hours to give them money so they didn't have to do those things.
I didn't sit there and think: 'It's nothing to do with me'. I worked - I lost my job 18 months ago because of this situation.
All we can say as a mother is I do my best. I say to them, 'This isn't right, this isn't good, you will end up in prison or dead - that's the reality.