Large Japanese bird

While driving to Kato I went through this large area of  harvested rice fields.  Five large white birds with back tail feathers and long beak were foraging in one field.  I have not seen this bird in Japan before.  I think it is an ibis or a crane, but am not sure.  They were walking slowly and pecking.   In the last photo, one bird started to cross the road to another field and the others followed.   I thought of driving down that road, but decided against it.  Maybe if I see them again, I will try to get a closer photo.