It barked at them
Very likely. One homeless person was invited to stay the night, they threw her out and stated that if she went back in to get her clothes, they would keep her there all night. The police sorted it out. The police spend quite a lot of time there. People have been taken out in handcuffs etc.
No problem. It barked at him when he knocked at the door late at night. Next day it barked over the hedge at him. Mum doesn't like him and is a bit afraid, the dog obviously picks up on this.
Thank you Jo. It used to be a quite community of people, some suffering from mental illness, some retired, but all got on well and helped each other. These new young people are causing real distress. I will pass your advice on to my mother.