Japan has long caught flak for being closed to asylum-seekers, and the deportation this week of two Kurds from Turkey — despite their U.N. recognition as "mandate refugees" — has brought the government under a fresh attack.

Ahmet Kazankiran and his son, Ramazan, were deported to Turkey on Tuesday, one day after they were detained when they reported to the immigration office to have their provisional release renewed. Their current situation in Turkey has yet to be confirmed.

The office of the U.N. High Commissioner for Refugees has described the deportation as "contrary to Japan's obligations under international law" and said it contradicts the humanitarian aid Japan extends to refugees and disaster survivors abroad.