Behavioural issues

Having so serious Behavioural issues with my 8yr old son that are only getting worse.

They started at the age of 6, he was a very beautiful kind hearted boy that I adored then suddenly he become so vial, violent, argumentative and it breaks my heart to even say this but honestly a child I cannot stand or even want to be around.

It was a very sudden change in behaviour, he just woke up one day in a bad mood that never went away but progressively gotten worse, his teacher don't have any concerns about his behaviour at school so myself and my younger daughter are the only ones experiencing this Behavioural change, its getting so bad that he is now much stronger then I am, his tackled me to the ground multiple times in rage and I'm getting more and more concerned the older he gets that I'm going to end up with much worse injury the stronger he gets.

I'm now having to dead lock the doors because he just leaves the house at any time he wishes, I once found him roaming the street at 10pm after I noticed the front door was wide open I went to check both my kids and found he wasn't in his bed, I asked him why he thought it was okay to just leave and he has this idea that he can do whatever his wishes and has a delusional belief he doesn't need permission, boundaries or rules.

I try to talk to him calmly about what the issues are but I don't even think he knows because he turns it into a argument that goes around in circles and it leaves me with more questions then answers.
His extremely hateful of rules and even me, he is very entitled and believes he has right to everything.

He has absolutely no control of his emotions and they are expressed in extreme forms even positive emotions are very full on and in your face.

I love my son to death but I'm beyond lost on what I can do to help him, and bring his old self back, I don't even know what caused the Behavioural changes in the first place

His currently in animal therapy, but it doesn't really help with the behavioural issues so I'm looking into some other options. But if there anymore I can do, does anyone had the same type of issues and found ways to work through the issues