 The hostility between the two groups continued, as "additional rounds of ethnic tension and violence flared periodically and led to mass killings of Tutsi in Rwanda, such as in 1963, 1967, and 1973".The establishment of the Rwandan Patriotic Front (RPF) and its invasion from Uganda furthered ethnic hatred.A ceasefire in these hostilities led to negotiations between the government and the RPF in 1992.