On Sunday, 30 January 1972 - in the Bogside area of Londonderry - British troops opened fire on civil rights demonstrators. Thirteen people lost their lives. Another died some time later from injuries his family say were sustained on the day. On Tuesday the Saville Inquiry will publish its report into those events.
Here, using archive images and eyewitness accounts from the day and immediate aftermath, see how the BBC reported what happened.
BBC archive audio from 30 and 31 January 1972.
Images courtesy: Rex Features, Getty Images, Press Association, Derry Journal/Larry Doherty.
Special thanks to The Museum of Free Derry.
Slideshow production by Paul Kerley. Publication date 14 June 2010.
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