The family of a man who lost an eye in a knife attack has appealed for calm after the incident triggered a wave of anti-immigrant violence in Northern Ireland, with masked men torching homes and vehicles.The appeal came as a Sudanese man appeared in court charged with attempted murder, and as United Kingdom Prime Minister Keir Starmer and politicians in Northern Ireland condemned the violence by "masked thugs" that had targeted ethnic minorities.Hundreds of protesters, many with their faces covered, had attacked police and burned vehicles in a number of locations across Northern Ireland on Wednesday after a video of the knife attack went viral."We want to make it absolutely clear that overnight unrest is not welcome, and peaceful protest is the only way forward," the family of the victim, Stephen Ogilvie, said in a statement."We have many migrants who make a deeply valuable contribution to our country .. and they still didn't care."Northern Ireland's first minister Michelle O'Neill described the violence perpetrated by the masked men as "nothing less than disgusting cowardice".The attack, which is currently not being treated as terrorism, comes at a time of heightened tensions in the United Kingdom following the murder of a student who was handcuffed by police as he lay dying from stab wounds after his killer, a Sikh man, falsely alleged a racist attack.It also follows repeated protests about immigration, with populist parties saying the UK's asylum policy had allowed dangerous men into the country.Amid online calls for more protests on Wednesday, Northern Ireland's police chief said an extra 200 officers were being deployed on the streets."These idiots didn't just target ethnic minority groups ..