In a new book about the 2012 attack on the U.S. consulate in Benghazi, a group of American commandos who were tasked with guarding the compound claim they were ordered to stand down during the attack, preventing them from rescuing Ambassador Christopher Stevens and others who were trapped inside. The book, titled 13 Hours, is scheduled to be released next week, but a copy was obtained by David Kirkpatrick of The New York Times.

According to the book, five members of a private security team say an unidentified CIA station chief ordered them not to intervene (against their protests) as the consulate was under attack by militants. The commandos say they eventually disobeyed the order, but not soon enough to save Stephens and another American who were both killed.

The group of commandos eventually did engage with fighters at the compound later that evening. Two members of the security team — former Navy SEALS who were hired as private contractors — were also killed in the fighting.

It's believed that the station chief gave the order to stand down on his own accord, and not on the authority of commanders elsewhere. According to the Times's description of the story, the CIA chief was hoping to rally support from local Libyan militias, believing they might step into rescue those inside the consulate, without the CIA needing to expose its position in the city. That support never came.

In a statement to the Times about the book, a U.S. intelligence official said, "there was no second-guessing those decisions being made on the ground” and “there were no orders to anybody to stand down in providing support.”

The book will likely reignite the long-running debate over the American response to the attack, and the level of protection given to the consulate. There have been many previous claims about what happened at the compound that night, and how U.S. commanders chose to respond to the unfolding attack, although many of the accounts remain unconfirmed, or have been debunked. In June of this year, U.S. forces captured Ahmed Abu Khattala, the man they say was instrumental in planning the attack.