Greece: At Nea Kavala camp, 'a concrete wall blocks the view and cuts out the sound'

In northern Greece, not far from the Greek-Macedonian border, the Nea Kavala migrant camp houses 1,200 people. It is one of the largest in the region. Isolated, not served by public transport, and now surrounded by a huge concrete wall, the camp is an "open-air prison" for its occupants.