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Eight Silver Stars have been awarded to American service members fighting ISIS

Silver Stars are the third-highest US military combat honor

Washington CNN  — 

One Army helicopter pilot flew a mission for 10 hours, five of them while wounded, in a high-risk effort to rescue American hostages.

Another continued a dangerous night-time mission deep in enemy territory despite sustaining extensive damage to his aircraft.

These are just some of the details contained in documents obtained by CNN. Eight Silver Stars, the third-highest US military combat honor, have been awarded to American service members fighting ISIS, CNN has learned. Two have previously been made public, but most of them have been kept under wraps due to the sensitive nature of the operations, including two more awarded earlier this summer.

Four of these citations remain so classified that no information is available about them, despite repeated attempts to obtain them.

But CNN has learned new details about two anti-ISIS operations gleaned from records of the combat awards. CNN has agreed to a Pentagon request to withhold the names of troops involved because many are still on active duty and there is concern about ISIS trying to track them down.

RELATED: Infographic: US military honors, explained

In one case, a Silver Star was awarded for a mission in July 2014 in which Navy SEALS and Army Delta Force commandos had tried to rescue American hostages held by ISIS in Raqqa, including journalist James Foley.

They didn’t succeed in rescuing the American captives, who had already been moved, and Foley was later executed by Jihadi John.

But in the effort, an Army helicopter pilot received the decoration for a “10-hour, classified, high-risk mission deep inside enemy territory.”

The pilot flew overhead for “five hours after being wounded during the initial assault.”

A Marine on the same mission was awarded a Bronze Star, bestowed for heroic achievement or service in ground combat, as he came into “close combat” with ISIS and “eliminated a grave threat.”

Another Silver Star was awarded in connection with a May 2015 raid inside Syria to capture top ISIS operative Abu Sayyaf, who ended up being killed in a firefight.

In that incident, considered one of the biggest intelligence hauls in the fight against ISIS, an Army pilot was decorated for a night-time “high-risk mission deep inside enemy territory.” He continued to fly for over an hour “despite sustaining intense battle damage to his aircraft during the initial assault.”

RELATED: US troops lost weapons to ISIS in firefight

Why valor is kept under wraps has everything to do with keeping troops safe and their counterterrorism tactics secret. “The two primary reasons are that the operation itself is classified or that the member is part of our special forces,” said Pat Mulcahy, the Defense Department official who helps oversees the awards program.

Mulcahy noted that since the 9/11 attacks, some 1,200 troops have received the nation’s top awards: the Medal of Honor, the Silver Star and the Service Cross.

Twenty percent of those awards – or some 240 – remain classified.

One Marine gunnery sergeant was awarded the Navy Cross for heroism during the attack on the US compound in Benghazi, Libya, in 2012, helping to save wounded colleagues, the documents reveal.

Since operations against ISIS began, it appears the percentage of secret operations is growing.

“Since June 2014, the services have awarded eight silver stars, half of them are either (because) the member was in a classified operation or they are a member of the Special Forces,” Mulcahy said.

One award did become public in extraordinary circumstances.

In February, Navy Senior Chief Edward Byers, a member of the secretive SEAL Team Six, stepped out of the shadows and into the glare of media and lights at a White House ceremony where he received the Medal of Honor – the nation’s highest award – from President Obama.

The President openly acknowledged the unusual occurrence: “Many of the operational details of his mission remain classified. Many of his teammates cannot be mentioned,” the President said.

Byers held off a Taliban fighter with his bare hands during a hostage rescue.

“Ed saved the lives of several teammates – and that hostage,” Obama noted.

The Navy says Byers remains on active duty. But the military will not say where he is, or what job he carries out. It’s a similar situation to so many others, who are working in the shadows despite their acts of valor.