March 12, 2010 -- Three Army officers have received letters of reprimand for failing to prepare adequate defenses for a combat outpost in Wanat, Afghanistan, where a mass Taliban attack in July 2008 resulted in the deaths of nine soldiers and 27 wounded, Defense Department officials confirmed to ABC News.

"These are essentially career-enders," said a military official of the letters of reprimand.

Two Defense Department officials said the actions are not yet final because the review that led to the letters of reprimand is still ongoing and the three officers have a period of time to respond and request reconsideration of the disciplinary action.

Among the three officers receiving the letters of reprimand is Capt. Matthew Myer, the company commander of the unit attacked at Wanat, who was awarded the Silver Star for his brave actions in repelling the attack. The Silver Star is the military's third highest award for bravery under fire.

However, the actions of Myer and two of his superior officers prior to the attack are what prompted the disciplinary action, namely not preparing adequate defenses for the newly built outpost that left it vulnerable to attack.

The senior officers at the time were battalion commander Lt. Col. William Ostlund, and brigade commander Col. Chip Preysler. Ostlund has since been promoted to colonel and is the deputy commander of the 75th Ranger Regiment. Preysler now works for the Joint Staff at the Pentagon.

Days after U.S. troops set up the outpost in remote eastern Afghanistan, hundreds of Taliban fighters conducted a surprise ambush on the facility.

A review of the battle completed in January by U.S. Central Command recommended disciplinary action against the company, battalion and brigade commanders responsible for the unit at Wanat.

Army Gen. Charles Campbell was tasked with determining whether disciplinary action needed to be taken against the three officers. Campbell's review still is ongoing and is expected to wrap up in mid-April.

Army Reviews Defenses in Several Afghan Battles

As the review continues, the three officers will have the opportunity to appeal the letters of reprimand. If the letters of reprimand remain in their files, they likely will mean an end to career advancement.

The letters of reprimand continue a recent trend of disciplining military commanders for their actions on the battlefield. These include the attacks on COP Keating and Ganjgal.

The Central Command report was the second review of the battle. An earlier Army report found no errors in the chain of command.

However, a new review was ordered after family members and members of Congress pressed for a new look at the circumstances leading up to the battle after an Army historian's research raised questions about potentially faulty planning of adequate defenses at the base.

CBS News was first to report the reprimands.