This might sound odd but sometimes you need to startle the child to break the tamtrum. HItting and biting are absolutely not allowed so if you say "NO" very loudly and that doesn't get his attention douse him with water(sometimes a hand flick of a few drops will do it). This usual gets a reaction from an out of control child. Dry him off and into time out he goes. Be firm and set a timer. Water doesn't hurt the child, but does get his attention. This works with animals too. If you don't like the idea of water, then get a track starter, a whistle, a gong. Your will will have to be stronger then his. You must make it absolutely clear that any hitting or biting will not be allowed and whatever you are doing ceases at that instant and into time out he goes. If you have to leave the shopping cart, so be it. If you have to leave the restaurant, so be it. If you have to leave grandma's, the party, the zoo, what ever it is, you leave immediately. The results of the tantrum must be clear cut and immediately applied. You must be firm and your resolve must be firm. Do not give in to whining, pleading, etc. The child must know that a certain behavior result in a certain consequence. You and your husband must agree on this as does your day care person. This strategy must be applied by all caregivers and without fail. I think a few times of this and he will stop. If this doesn't work, then I think you need to learn where he learned this behavior. You may have to change your daycare situation. Maybe you should watch how your daycare person interacts with your child and other children. Just a suggestion.