“As Yemen faces various internal challenges, it is more crucial than ever that violations of international human rights law are not swept under the carpet,” said Rupert Colville, the spokesperson for the UN High Commissioner for Human Rights.Speaking to journalists in Geneva, he noted that to date “no official investigation has been initiated into the alleged excessive use of force.”According to interviews conducted by the UN Human Rights Office (OHCHR), the protesters on 7 and 9 September were armed only with sticks, stones and umbrellas, when security forces opened fire with live ammunition without warning. Those killed include a farmer, an ambulance driver, an airport worker and students.An additional 67 people were reportedly injured, according to OHCHR, including 33 by live ammunition and others as a result of use of tear gas.A prompt, impartial investigation would “send a strong signal of deterrence to perpetrators and ensure that victims’ right to justice and remedy is upheld,” Mr. Colville said. Yemen has recently emerged from a complex UN-backed transition, but recent months have been marked by violence and unrest in some parts of the country. The UN spokesperson also reiterated calls for Yemenis on all sides of the political divide to renounce the use of violence and to participate in the ongoing national processes to avoid further instability and bloodshed. Yemen has recently emerged from a complex UN-backed transition, but the past few months have been marked by violence and unrest in some parts of the country. According to press reports, Sana’a has been gripped by rival protests since last week as pro- and anti-Government demonstrators have faced off throughout the city.