Three year old behaviour

My three year old is an outgoing boy, so smart, and genuinely funny. However, he has an aggressive side, where he hits, scratches, bites us, his sibling and also at nursery. We address this behaviour by taking him away, address his feelings and say hand are not for hitting we do this with hands instead etc.

However, his behaviour just seems to be getting worse. Always incidents at nursery, something at home. He just doesn’t listen. I don’t know what to do and was wondering if there is any advice to address this as it is keeping me up at night.

Is this age appropriate or should we be escalating this?