By Stephanie Nebehay
GENEVA (Reuters) - The United Nations human rights office called on Mexico on Friday to properly investigate large-scale extrajudicial killings and bring those responsible to justice, including higher-ranking military officers.
Mexico's military has been accused on multiple occasions of extrajudicial killings and torture during a decade-long war against the country's brutal drug cartels.
Last week a Mexican judge acquitted three military personnel of the extrajudicial killing of 15 suspected gang members during a confrontation in June 2014 in Tlatlaya.
"We are deeply concerned that almost two years after the commission of serious human rights violations in Tlatlaya in Mexico State, including the alleged summary execution of at least 12 people, the case remains mired in impunity and victims continue to be denied their rights to justice and the truth," U.N. human rights spokeswoman Ravina Shamdasani told a briefing.
"We call on the Mexican authorities to ensure a thorough, effective, impartial, independent and prompt investigation into this emblematic case," she said.
Investigations should be extended to all those who may be responsible, "including higher-level military officers who may hold command responsibility", as well as anyone who may have tampered with the crime scene, she added.
Authorities said at the time that the dead were suspected drug gang members and that the military had acted in self-defense. A total of 22 people died in the incident.
But months later, foreign media reported that there was evidence of extrajudicial executions, a version later upheld by Mexico's CNDH national human rights body.
Shamdasani also expressed disappointment with a lack of progress in solving another high-profile case, that of the apparent massacre of 43 trainee teachers in the southwestern city of Iguala in 2014.
A panel of international experts last month accused the government of President Enrique Pena Nieto of undermining their investigation into the fate of the teachers.
(Reporting by Stephanie Nebehay; Editing by Gareth Jones)