MEXICO CITY (Reuters) - Mexican troops and police committed two extrajudicial killings while confronting presumed fuel thieves in the central state of Puebla in May 2017, a Mexican human rights group said on Wednesday, adding to allegations of abuse against the military.

A report by the National Human Rights Commission (CNDH) said police and troops manipulated the scene by placing high-caliber firearms beside the two bodies. Eight other people died and 13 people, including four minors, were detained with excessive force, the report said.

Neither the defense ministry nor the Puebla police force responded to requests for comment. The state government declined to comment.

The military has assumed some police duties in Mexico for more than a decade, working to combat rising drug violence that contributed to a record 31,000 homicides in 2017. Their increased responsibilities have coincided with accusations of human rights violations including extrajudicial killings, kidnappings and torture.

“As a result of its investigation, the CNDH has the evidence to show grave violations to human rights and personal freedom,” the group said of the reported deaths in Puebla.

The CNDH urged state oil firm Pemex to cooperate in investigations and not let its property be used to hold detainees.

Pemex did not immediately respond to requests for comment.

The CNDH previously found that armed forces were involved in the murder of four people in the state of Tamaulipas in 2014, and that soldiers arbitrarily executed two people after an illegal raid in 2016.

“This case is one more example of how the Mexican military violates human rights,” Amnesty International said in a statement in response to the CNDH report. “It’s time for the armed forces to return to their barracks.”

The CNDH called on the Mexican attorney general’s office to investigate, and said national and state officials should provide reparations for the victims.

Mexico’s congress passed a controversial security law last year that would lay out the rules under which the armed forces can operate in the battle with organized crime. The law was strongly criticized by opponents who fear it could open the door to more abuses.

Mexican President Enrique Pena Nieto has said the law will not be implemented until it is reviewed by the Supreme Court.