The Obama administration has vowed to capture or kill the masked militant who was seen in multiple Islamic State hostage beheading videos, and now that "Jihadi John" has been identified as 26-year-old Briton Mohammed Emwazi, Attorney General Eric Holder says the U.S. is readying to “hunt” him down.

“Whether it’s through the use of our military, through the use of our law enforcement capacity, if you harm Americans, it is the sworn duty of every person in the executive branch to find you and hold you accountable,” Holder said in an interview with CNN.

“It doesn’t matter where you are, we’ll find you, we’ll hunt you down, and we will hold you accountable.” When pressed on whether the U.S. would send troops to Syria to locate Emwazi, Holder said he “wouldn’t put anything off the table.”

“Any time any American is harmed anywhere in the world, the United States government is going to be going after that person,” President Barack Obama said in an interview with Seattle’s KOMO-TV on Thursday. “And eventually, if you hurt an American, you’re going to be brought to justice in some fashion.”

Obama and Holder’s comments come after British Prime Minister David Cameron also vowed to track down the jihadist militant. “When there are people anywhere in the world who commit appalling and heinous crimes against British citizens, we will do everything we can with the police, with the security services, with all that we have at our disposal to find these people and put them out of action,” Cameron said in a statement Friday, according to a report by Reuters.

Though the Washington Post was the first to reveal the identity of “Jihadi John” on Thursday, U.S. intelligence officials say British security officials knew his identity months ago.

Emwazi, who was born in Kuwait and raised in London, is reportedly the British-accented masked man from the videos in which American journalists James Foley, Steven Sotloff, American aid worker Peter Kassig, British aid worker David Haines and British taxi driver Alan Henning were murdered.