Marines involved in a controversial experiment evaluating a gender-integrated infantry unit say they feel betrayed by Navy Secretary Ray Mabus after he criticized the results of a nine-month study that found women are injured more frequently and shoot less accurately in simulated combat conditions.

“Our secretary of the Navy completely rolled the Marine Corps and the entire staff that was involved in putting this [experiment] in place under the bus,” said Sgt. Danielle Beck, a female anti-armor gunner with the task force.

Mabus questioned the findings of the research after a four-page summary of the results was released Thursday, saying he still thinks all jobs in the Marine Corps should be opened to women. He said results that found women were more than twice as likely to be injured and ultimately compromise a unit’s combat effectiveness were an “extrapolation based on injury rates, and I’m not sure that’s right,” he told NPR.

Sgt. Joe Frommling, one of the Marines who acted as one of Beck’s monitors for the experiment, said he was frustrated with the secretary’s comments.

“What Mabus said went completely against what the command was saying the whole time,” said Frommling. “They said, ‘Hey, no matter what your opinion is, go out there and give it your best and let the chips fall where they may.’”

“All the work that the task force did, the rounds that we shot, didn’t mean anything if he had already made up his mind,” he added.

Capt. Patrick McNally, a spokesman for the secretary, said Mabus had no further comment beyond his earlier remarks and “remains committed to opening combat fields to women.”

Last week, the Marine Corps released the results of the nine-month experiment, known as the Ground Combat Element Integrated Task Force, which examined and tested the effectiveness of a gender-integrated infantry unit. The results, in short, determined that women were injured at a higher rate and did not do nearly as well as their male counterparts in the majority of the tested areas.

“It started out with a fairly large component of the men thinking ‘This is not a good idea’ and ‘Women will never be able to do this,'” Mabus said in the Friday interview with NPR. “When you start out with that mind-set, you’re almost presupposing the outcome.”

The task force was stood up in October 2014 and consisted of roughly 300 men and 100 women broken down into a number of smaller units. Each job that is currently closed to women, known as combat arms, was represented. Artillery, tanks, amphibious and armored vehicles all had a component. The task force then conducted training exercises like any other. Its mission was to hold a number of trials that would evaluate the performance of a female-integrated ground task force.

“If you were to look at our training plan and how we progressed from October to February, you’re not going to find any evidence of institutional bias or some way we built this for females to fail,” said one Marine officer who participated in the experiment.

The officer, who asked to remain anonymous because of his active-duty status, explained that for the first five months of the experiment the Marines of the task force trained as a unit in North Carolina to prepare for the testing phase in California. This phase of training is known as “the work-up,” with the second phase in California — where the trials would be held — acting as the deployment.

“We consulted physical trainers from [the school of infantry] to help develop an appropriate hike plan, and we fired roughly a year’s worth of ammo for a regiment in a quarter,” the officer said, referring to the massive amounts of ammunition used to train the relatively small task force at Camp Lejeune. “In the time that we had, there wasn’t a day wasted when it came to training for California . . . From the top down, we were trying to level the playing field.”

The main components of the task force were Alpha and Weapons companies. Alpha would be a female-integrated rifle company, or “line” company, while the Weapons company would consist of three female-integrated sections: mortars, machine guns and an anti-armor section.

A weapons company in an infantry battalion, arguably, has the most rigorous set of requirement in combat. Each section in the company is dedicated to hauling a weapons system that regular rifle companies don’t have to carry—from 90-pound 81mm mortars to 85-pound .50-caliber machine guns.

Beck, a Weapons Company Marine in the Task Force, was one of 17 women and 21 men who were left in the company at the experiment’s conclusion in August. According to Marines involved in the experiment, numbers fluctuated frequently as those who volunteered to participate could drop at any time. A large number of men in the company dropped because they were promised an assignment to any unit in the Marine Corps for participating in the experiment. This caused the company to shrink considerably from its initial strength of around 90 volunteers in October.

“Every day we were training,” said Beck. “We didn’t know what we were going to expect when we got to Twentynine Palms, but the training that we did do got us physically ready and mentally in the mind-set for what we’re going to do.”

Though the entirety of Weapons Company, men and women, trained to the same standard before deploying to California for the evaluation period of the test, another criticism leveled by Mabus was that the women probably should have had a “higher bar to cross” to join the task force.

To Beck, a 30 year-old who was one of the strongest women in the company, Mabus’s remarks were insulting.

“Everyone that was involved did the job and completed the mission to the best of their abilities,” said Beck, adding that Mabus’s remarks about the type of women in the experiment were a “slap in the face.”

“The caliber of the women in Weapons Company are few and far between in the Marine Corps,” she added. “They are probably some of the most professional women that anybody will ever have chance to work with, and the heart and drive and determination that they had is incomparable to most women in the Marine Corps.”

Of the men and women who were in Weapons Company and participated in the majority of the experiment’s trials, the women performed better than the men on the Marine Corps-wide physical-fitness test. The average score for the men in Weapons Company was 244 out of 300 while the women’s average was 283, according to documents obtained by The Washington Post. For an average all-male infantry unit, physical-fitness scores are usually in the 260s.

In Weapons Company, all of the women who were evaluated against their male infantry counterparts had passed the same School of Infantry the men had attended.

In 2013, the Marine Corps opened its enlisted infantry school to female volunteers. From September 2013 to June 2015, 144 of the 401 females volunteers had passed the once male-only school.