Updated

A Mexican judge has ordered federal authorities to investigate whether army commanders played any role in the killing by soldiers of 22 suspected criminals at a warehouse three years ago, a case that became one of the country's biggest scandals over allegations of human rights abuse.

The ruling said the federal Attorney General's Office did not investigate a purported military order issued before the incident in which soldiers were urged to "shoot down criminals in hours of obscurity." The federal judge's ruling was issued Aug. 1, but did not become public until Tuesday.

The government's human rights agency charged that at least a dozen and as many as 15 of the suspects were executed after surrendering to an army patrol following a June 2014 gunbattle in the town of Tlatlaya.