It's 30 years since a massacre of Bosnian Muslims during the war in the former Yugoslavia.

The Srebrenica massacre, recognised by the United Nations as a genocide, was the shocking climax of the war in Bosnia.

In 2014, Louise Hidalgo talked to Hasan Nuhanović whose father, brother and mother were among the 8,000 Bosnians killed.

Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from the death of Adolf Hitler, the first spacewalk and the making of the movie Jaws, to celebrity tortoise Lonesome George, the Kobe earthquake and the invention of superglue. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: Eva Peron – Argentina’s Evita; President Ronald Reagan and his famous ‘tear down this wall’ speech; Thomas Keneally on why he wrote Schindler’s List; and Jacques Derrida, France’s ‘rock star’ philosopher. You can learn all about fascinating and surprising stories, such as the civil rights swimming protest; the disastrous D-Day rehearsal; and the death of one of the world’s oldest languages.

(Photo: Graves of those killed in the Srebrenica massacre. Credit: Pierre Crom/Getty Images)

The 1977 murder of Father Rutilio Grande sent shockwaves through El Salvador. The 48-year-old Jesuit priest was an outspoken champion of the poor in the deeply divided central American nation.

In the immediate aftermath of his murder, the Archbishop of San Salvador, Oscar Romero, took the unprecedented step of holding just one single mass, ordering all other churches in his archdiocese to cancel theirs. Romero also refused to attend any government functions.

Father Grande was one of the first priests to be killed by security forces in the years leading up to the bloody Salvadoran civil war.

His murder marked a turning point as the church became increasingly involved in promoting social justice, and other priests became more outspoken against the government's repression of dissent.

Mike Lanchin has been hearing from Gabina Dubon, who worked with Father Grande in his rural parish, and to theologian and author, SisterAna Maria Pineda. This is a CTVC production for BBC World Service.

Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from the death of Adolf Hitler, the first spacewalk and the making of the movie Jaws, to celebrity tortoise Lonesome George, the Kobe earthquake and the invention of superglue. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: Eva Peron – Argentina’s Evita; President Ronald Reagan and his famous ‘tear down this wall’ speech; Thomas Keneally on why he wrote Schindler’s List; and Jacques Derrida, France’s ‘rock star’ philosopher. You can learn all about fascinating and surprising stories, such as the civil rights swimming protest; the disastrous D-Day rehearsal; and the death of one of the world’s oldest languages.

(Photo: Father Rutilio Grande. Credit: Camilo Freedman/APHOTOGRAFIA/Getty Images)

In May 1974, scratch cards went on sale for the first time in the US State of Massachusetts.

Free giveaway and coupon games from stores had been commonplace across the USA during the 1950s and '60s – but players could easily cheat.

The mathematician John Koza was hired to make the games more secure; he succeeded in making the modern-day scratch card. He tells Johnny I’Anson how he convinced the state-run lotteries to use his invention to offer cash prizes.

Eye-witness accounts brought to life by archive. Witness History is for those fascinated by the past. We take you to the events that have shaped our world through the eyes of the people who were there. For nine minutes every day, we take you back in time and all over the world, to examine wars, coups, scientific discoveries, cultural moments and much more. Recent episodes explore everything from the death of Adolf Hitler, the first spacewalk and the making of the movie Jaws, to celebrity tortoise Lonesome George, the Kobe earthquake and the invention of superglue. We look at the lives of some of the most famous leaders, artists, scientists and personalities in history, including: Eva Peron – Argentina’s Evita; President Ronald Reagan and his famous ‘tear down this wall’ speech; Thomas Keneally on why he wrote Schindler’s List; and Jacques Derrida, France’s ‘rock star’ philosopher. You can learn all about fascinating and surprising stories, such as the civil rights swimming protest; the disastrous D-Day rehearsal; and the death of one of the world’s oldest languages.

(Photo: The original scratch card. Credit: Massachusetts State Lottery)