This is a terrible and very sad news. I remember Avner as a friend although I knew him only for one year, when we shared our PostDoc there in 2002.
He was really a very nice, enthusiastic, friendly, patient, brilliant, intelligent, deep and ironic friend and colleague: a beatiful person and a gentle spirit.
That kind of person that after one hour together you would like to have him as a friend for ever. This is very very sad.
My deepest condolences to his family.