American journalist Steven Sotloff, center with black helmet, talks to Libyan rebels on the Al Dafniya front line in 2011. (Photo by Etienne de Malglaive via Getty Images)

Secretary of State John Kerry said the murderers of journalists James Foley and Steven Sotloff will be held accountable, “no matter how long it takes.”

“Yesterday, the world bore witness again to the unfathomable brutality of ISIL terrorist murderers when we saw Steven Sotloff, an American journalist who left home in Florida to tell the story of brave people in the Middle East, taken from us in an act of medieval savagery by a coward hiding behind a mask,” Kerry said in a statement released by the State Department. “This young man was a driven and courageous journalist, reporting from places like Syria, Libya, and Egypt. Steven Sotloff’s reporting was as empathetic as his killers are evil. He focused on the stories of average people trapped in war, and documented their day-in and day-out struggle for dignity. Like Martha Gellhorn, he chronicled humanity in the face of inhumanity, and he told the story of enormous generational events as if they were happening to someone you knew from your own life.”

Foley and Sotloff were both beheaded by men claiming to be members of the Islamic State, a militant group that uses crucifixions and beheadings as part of a campaign to establish a religious caliphate is the Middle East. Video of Foley’s murder emerged in late August, while Sotloff’s surfaced yesterday. Foley was captured in Syria in November 2012, while Sotloff disappeared in August 2013.

An attempt was made to save Foley, Sotloff and other hostages earlier this summer, according to the White House, but it was unsuccessful.

Read Kerry’s full statement below:

Yesterday, the world bore witness again to the unfathomable brutality of ISIL terrorist murderers when we saw Steven Sotloff, an American journalist who left home in Florida to tell the story of brave people in the Middle East, taken from us in an act of medieval savagery by a coward hiding behind a mask.

There are no words strong enough to express the sorrow we feel for his family, particularly his mother, whose heartbreaking video plea spoke to every single parent who has ever worried about a son or daughter who goes to dangerous places to do the work they love.

This young man was a driven and courageous journalist, reporting from places like Syria, Libya, and Egypt. Steven Sotloff’s reporting was as empathetic as his killers are evil. He focused on the stories of average people trapped in war, and documented their day-in and day-out struggle for dignity. Like Martha Gellhorn, he chronicled humanity in the face of inhumanity, and he told the story of enormous generational events as if they were happening to someone you knew from your own life.

For so many who worked so long to bring Steven and the other Americans home safely, this was not how the story should’ve ended. It’s a punch to the gut. The U.S. Government has used every military, diplomatic, and intelligence tool we have, and we always will. Our special operations forces bravely risked a military operation to save these lives, and we’ve reached out diplomatically to everyone and anyone who might be able to help. That effort continues, and our prayers remain – as they always are – with the families of all hostages who remain trapped in Syria today.

Barbarity, sadly, isn’t new to our world. Neither is evil. We’ve taken the fight to it before, and we’re taking the fight to it today. When terrorists anywhere around the world have murdered our citizens, the United States held them accountable, no matter how long it took. And those who have murdered James Foley and Steven Sotloff in Syria should know that the United States will hold them accountable too, no matter how long it takes.