NEW: Slaughtered Mormon women and children were targeted, shot point-blank in Mexico killings, contradicting earlier reports

New details cast doubt on the official account of the Mormon killings in Mexico, with evidence indicating that some victims were shot at point-blank range, the New York Post reports.

Nine women and children of a Mormon family were gunned down Monday as they were traveling in a convoy of sport utility vehicles in the Mexican state of Sonora, about 70 miles from Arizona.

Mexican authorities have said the gunmen misidentified the vehicles as belonging to a rival drug cartel.

But an American law enforcement official told the New York Post many of the victims were removed from their cars and then shot, which suggests they were targeted.

Adding fuel to the controversy, Mexican authorities have also reportedly denied American investigators access to the crime scene.

“It’s kind of disturbing that the FBI has had no access to the crime scene, which is probably a disaster already because the Mexicans have allowed families to remove the bodies,” the American law enforcement source told the New York Post. “Any evidence that could have been gathered is probably destroyed.”

At a news conference this week, Mexican Army Chief of Staff Hector Mendoza reportedly said one of the cartels thought the other was encroaching on their territory; two cartels had attacked each other the day before the killings.

Mendoza added that he believed the family was not targeted because he said the gunmen allowed some of the children to escape.

Sources claimed told the New York Post that the Mexican federal government simply is not interested in investigating drug trafficking.

“They will go to any extreme to cover everything up,” the source told the Post. “It’s completely corrupt, and it’s only going to get worse.”

An FBI spokesman did not directly address the allegations that Mexican authorities were obstructing American investigators, instead offering only this comment: “The FBI continues to engage with our US government and Mexican law enforcement partners. We have offered assistance and stand ready to assist in the wake of this tragedy.”

Victims’ families also are doubtful of the official account. As reported by the Washington Post, family spokesperson Julian LeBaron told the Mexican newspaper El Universal that the gunmen had to know the victims were women and children. One of the surviving children said one of the mothers had exited her vehicle with her hands in the air before she was shot.

Mormons have lived in this region of Mexico since the 1890s after the U.S. government began outlawing polygamy.

The Mormon families who live there have long clashed with drug cartels and have resisted extortion attempts by traffickers.

A cartel murdered Julian LeBaron’s brother in 2009 after protesting the kidnapping of their younger brother, who had been held for $1 million ransom. The family refused to pay and the child was later released.

“These are not isolated incidents,” Julian LeBaron wrote in a 2010 Dallas Morning News op-ed. “Throughout our nation, countless people have lost their lives or their security in a similar manner, while politics of confusion and volumes of magic words appear to have more sway than reality.”

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