Autism and coping with emotions

Hi All, I'm a sister to a wonderful brother ,18 years, who is Autistic. He can communicate however expressing himself through jumping and clapping his hands when he gets angry. He usually does this when she hears loud noises for example my son crying or nursery rythems being played or someone being told off. 

My concerns are that the anger is becoming worse as he has started to throw objects, and boarded on hitting family members. He means well and when calm apoloises for his actions but there are also times where he makes remarks such as ' I hate ...' or 'I could hurt you'. I can see he is having difficultly controlling or expressing his emotions and wondered how others have dealt with this behaviour and is there a need for therapeutic intervention. 

Our mother died when my brother was 16 years she was his sole career and support network. We have tried to do the best we can to support him as he now has a carer, travel trained and able to do most things himself. If we are able to assist or channel his emotions in a different way it may help him cope better in the future. 

Many thanks for any advice, experiences and support