Ask to talk to the teacher again and find out what s/he means by him becoming a 'school refuser.' It is very irresponsible of a teacher to suggest this possibility without explaining the reasons for thinking it.
Ten and half is considered adolescent by child therapists and most doctors, so he undoubtedly has some overwhelming hormones affecting his moods and behaviour. If you feel uncomfortable with the language he uses, ask him to substitute the worst words as they are unacceptable to you. But a second skin is a good thing to grow, as he doesn't mean most of what he says.
It's very important (as others have said) that he thinks you are able to take his angry feelings. He must feel that you are there, no matter what he says or does. Have you tried re-iterating the things he says, reflecting them back to him, so he knows you are listening calmly and are thinking with him? He says 'you are a horrible old witch.' You say 'you think I'm mean and nasty, like a witch?' 'Yes, I hate you.' 'You sound really angry...' Just opening up possibilities for him so he might talk a bit; let him shout, even, he might say something illuminating.
Unconditional love and containment are what he's after so let him have those. But also make boundaries, explaining that you love him but certain language and behaviour are not allowed in your home and if he continues, there will be sanctions: no pocket money, no tv, no computer etc. Sending him to his room won't work. Take away what he values, for a very short time at first, if he appears to be uncontrolled or completely unresponsive.
If none of this works, get help from a child psychotherapist. Problems with dad???