Following through with a threat made two weeks ago after the beheading of American journalist James Foley, ISIS has reportedly beheaded a second American journalist covering Iraq and Syria.

Steven Sotloff is the second American journalist to be executed publicly by ISIS after the group has demanded American airstrikes against the terror group and their controlled lands to cease.  ISIS released a video of the beheading, similar to that of the video showing the execution of James Foley, but the video is currently being analyzed for authenticity.

Sotloff, 31, was a graduate of the University of Central Florida and wrote for TIME as well as other publications.  According to NBC News, he went missing in Syria in August 2013.

This news comes one week after Sotloff’s mother, Shirley Sotloff, released her own video pleading to ISIS for the release of her son from captivity.  “I want what every mother wants,”  she said in the video, “to live to see her children’s children. I plead with you to grant me this.”

The video from ISIS reportedly shows Sotloff, dressed in an orange jumpsuit similar to the one Foley had worn, while a man in a black mask says, according to the Guardian, “I’m back,” signalling this may be the same masked man who had executed Foley.

After the execution of Sotloff, the video ends with the killer demanding an end to the American airstrikes, while showing another kneeling hostage.  Some sources are reporting this other hostage is a British citizen named David Cawthorne Haines.

President Obama said after the beheading of Foley that he and his administration were appalled by the video, while also saying the violence “shocks the conscience.”  According to the Hill, Obama also said, “We will be vigilant and we will be relentless.  When people harm Americans anywhere, we do what is necessary to make sure justice is done.”