The British defence ministry said on Thursday it was in contact with lawyers acting for the families of the 13 Irish demonstrators killed during a protest in the Northern Ireland town of Londonderry in 1972, an outrage that became known as "Bloody Sunday." A 12-year-long investigation ruled in 2010 that British soldiers had been entirely to blame for the slaughter.

Prime Minister David Cameron said the report had proven the deaths had been "unjustified and unjustifiable." The Bloody Sunday Inquiry, authorized by Britain's government in 1998, was seen as a key step to heal wounds left from Northern Ireland's four-decade conflict that left 3,700 dead.