Hi, I have a 5 year old rescue cross-breed (our guess is Jack Russell / Staffy) and she's suddenly become aggressive towards other dogs in the past couple of weeks. She used to be friendly with all dogs, but now growls and snarls at dogs who are far away as soon as she sees them, and lunges at dogs which we cross paths with and it only seems to be getting worse. I have tried training techniques such as distracting her with treats, which doesn't work because she is too focussed on other things in her surroundings, trying to walk on, telling her off... none of which is helping. She always walk on the lead, as she isn't very obedient. I try not to tense up on the lead because they say the dog can sense it, but I feel as though I have no choice as she chooses to lunge anyway. She hasn't had any bad experiences with dogs recently, my only guess is that she had a bad experience before we adopted her but I don't know why there has been a sudden onset of apparent aggression. Also, I met with a friend and her dog to see if a formal greeting with a well behaved dog would help, but she continued to be aggressive and once she sniffed the other dog, she actually bit her (the other dog is absolutely fine) which absolutely broke me as this is something she never would have done in the past. If anyone has any advice whatsoever PLEASE suggest it, because things are just getting worse and I'm worried for the future. Thank you.