This week, the U.S.-backed campaign against ISIS strongholds in Syria yielded a landmark victory.

After months of fighting, U.S.-backed troops say they've taken control of the Islamic State's capital Raqa.

We're seeing celebrations in the streets.

While the fighting may be over, eight groups say the area is on the brink of a humanitarian crisis.

As most of the city lies in rubble, thousands of residents are now living in refugee camps outside its borders.

For three years, the citizens of Raqa board the brunt of ISIS terror,

but we really heard their stories because our journalists couldn't get there.

A group of citizen journalists known as Raqa is being slaughtered silently risked their lives

to break that silence to show the world how the people of Raqa were oppressed

and murdered under the world's radar. Anonymous members of the group inside the city

sacrificed themselves to smuggle photos, videos, and stories to their comrades who had fled to

Turkey, Germany, and elsewhere. Matthew Heinemann is the director of City of Ghosts,

a documentary that tells the story of Raqa is being slaughtered silently.

Abdel Aziz al-Hamsa is co-founder and spokesman for the group, which we will refer to as

RBSS.

Aziz told us when we spoke to him last summer that it didn't take long for its members to

fall under the guns of ISIS.

Two weeks after we started our organization, ISIS announced in the mosques, that everyone

was working with RBSS should be executed.

A month after we started, they arrested one of our colleagues

and later on he was executed. Thousands of people were arrested because they just put on our

Facebook page. Later on, they arrested the father of my colleagues and the co-founder of RBSS, and then

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