biting is very normal for toddlers. i assume he's a toddler. they do not have the vocabulary or ability to express themselves. they feel frustration and don't know how to express it appropriately.
the teachers need to be proactive. chances are they have dealt with a "biter" before because it is very common. you anticipate when the child will bite and help them learn appropriate ways to handle the situation. for example, you should never allow a "biter" to be alone in the block area with other children. it's asking for trouble. you sit and play with them. if you see him get frustrated, you immediately jump in and model appropriate behavior. help the child label feelings. "I see you are mad that he took your block. You tell him no!"
toddlers don't know how to share, and developmentally shouldn't be expected to. of course we try to teach them, but our expectations need to be realistic. the class needs to provide enough activities to spread the children out and to keep them stimulated. sensory activities like playdough, water play, sand table, etc... are often very helpful in soothing and occupying toddlers.
and everyone involved needs to understand that it is common, and will eventually pass. when it does happen, you tend to the victim first. asking the child who bit to help comfort the other child may help build empathy and help them see first hand the effects of his actions. timeout can be utilized to to keep the "biter" out of trouble while you tend to the injured child. but timeout does not teach the toddler the skills he needs to cope and avoid biting all together.
you dont say how old he is? but as he is in Daycare I guess hes very young, perhaps the Daycare are not paying enough attention, how is the supervision, is there a way you can check it out ,very often children are left to their own devises and get bored, time out is a good solution , but if he doesnt do the biting anywhere else the problem lies there.