Events marking the 40th anniversary of Argentine human rights group the Mothers of Plaza de Mayo have been taking place in Buenos Aires.
Each week for the past four decades the Mothers - wearing white headscarves - have marched on the square in front of the presidential palace.
They are demanding to know what happened to their children during the military rule in 1976-83.
Human rights groups say about 30,000 people were killed during that period.
Argentine President Mauricio Macri has been criticised for questioning the number of victims of the junta.
The group was born on 30 April 1977, when 14 women gathered for a protest rally on the square near the Casa Rosada Presidential Palace.
Since then many more member have joined, and rallies have been held every Thursday.
Many of them are now old and frail, but their long protest has drawn international attention to the abuses by the junta.
The mothers may never know what happened to their children, but the organisation has influenced and supported groups across Latin America and beyond, BBC regional editor Candace Piette says.