You dont tell us what country you are from but I will assume you are in the US now, I am wondering if it is his way of getting attention from the other children, does he speak some English? It is a rather difficult transision for children to come to another country, children do learn languages very quickly once he is able to communicate better I think it will change so be patient , you may have to be firm and do time outs for the hitting of other children, do the timeouts as this will be understood more than just talking. Good luck in your new country..