LOS ANGELES: Four US servicewomen, including two who won Purple Hearts in Afghanistan, sued the Pentagon on Tuesday over its policy barring women from ground combat.

Backed by rights watchdog the American Civil Liberties Union (ACLU), they slammed the policy as an “injustice to the women ... who continue to put their lives on the line for their country.”

“Ever since I was a little girl I wanted to be an Air Force pilot, and I have proven my ability every step of the way,” said Major Mary Jennings Hegar, a rescue helicopter pilot who flew Medevac missions in Afghanistan.

Her aircraft was shot down in 2009 while rescuing three injured soldiers, and she had to fight, returning fire and sustaining shrapnel wounds. She was awarded the Purple Heart and Distinguished Flying Cross with Valor.

“The ability to serve in combat has very little to do with gender or any other generalisation. It has everything to do with heart, character, ability, determination and dedication,” she said, cited in an ACLU statement. “This policy is an injustice to the women who have come before us and who continue to put their lives on the line for their country.”

Women are still barred from ground combat units, although female troops have found themselves in combat anyway over the past decade in Afghanistan and Iraq, with more than 140 killed on the battlefield.

In February, the Pentagon announced incremental changes that will allow women to serve in more than 14,000 jobs, mostly in the Army and Marine Corps, that had previously been closed to female service members.

But the overall prohibition against women in ground combat remains, denying women the chance to join infantry and armor units as well as special forces.

Tuesday's lawsuit was filed in federal court in San Francisco, by the four servicewomen and the Service Women's Action Network, represented by the ACLU's Northern Californian office and law firm Munger, Tolles and Olson.

It cites Defense Secretary Leon Panetta as the defendant, according to a copy of the lawsuit seen by AFP.

Pentagon spokesman George Little said Panetta was committed to expanding women's roles in the US military.

“It's really not my place to comment on pending litigation,” he said, when asked about the San Francisco lawsuit.

But he said Panetta “remains very committed to examining the extension of roles for women in the US military and he's done so.

“On his watch, some 14,500 positions have been made been available to women, and he has directed the services to explore the possibility of opening additional roles for women in the military.

“So I think his record is very strong on this issue. The recent openings that I just referred to are really the beginning and not the end of the process, and we expect that process to continue”

Besides Hegar, the other plaintiffs, who all served in Afghanistan, are Marine Captain Zoe Bedell; Army Staff Sergeant Jennifer Hunt, who won a Purple Heart after her vehicle was hit by a roadside bomb; and Marine First Lieutenant Colleen Farrell.

“These women served their country bravely and honorably and have demonstrated their ability to distinguish themselves under fire just as much as their male comrades,” said ACLU lawyer Ariela Migdal.

“This antiquated policy doesn't reflect the nature of modern warfare or the actual contributions of women in uniform,” she added.