The largest search operation to date for a 6-year-old boy with autism who went missing in northern Germany nearly a week ago was carried out on Sunday. Police, soldiers, firefighters, members of the THW civil protection agency and hundreds of volunteers banded together to scour an area centred near Bremervörde, a town to the west of Hamburg. In all, about 1,200 people took part in the hunt for the boy named Arian. But by evening there was still no sign of him. Arian left his parents’ house alone on Monday evening. A surveillance camera filmed the boy running towards a neighbouring forest. The …