Istanbul police have broken up the 700th weekly vigil by Turkish mothers demanding accountability for disappearances of relatives since the 1980s. Tear gas was fired and dozens were detained while defying a protest ban. Police dispersed a group known as "Saturday Mothers" as it headed for Istanbul's Galatasaray Square, prompting Human Rights Watch (HRW) to describe Saturday's incident as "cruel treatment of families seeking justice for state crimes."One of those briefly held by police was an 82-year-old mother, Emine Ocak (pictured above), whose son Hasan disappeared in 1995 after being taken into custody, then aged 30.Read more: Turkey's silent 'Standing Man'...