An overwhelming majority of killings of journalists across the world go unpunished, a United Nations agency reported on Wednesday. “Impunity for killings of journalists remains unacceptably high at 86 percent,” said UNESCO, the United Nations cultural organisation whose brief includes media issues. UNESCO called for “all necessary measures to ensure that crimes committed against journalists are properly investigated and their perpetrators identified and convicted.” The organisation called the global immunity rate for journalist killings “shockingly high” in a report to coincide with the Intern…