The U.S. military’s senior noncommissioned officer issued a blunt warning to the Islamic State in Iraq and Syria (ISIS): Surrender or die.

“ISIS needs to understand their two options when facing us: surrender or die! Surrender & we will safeguard to due process. Otherwise we will kill with extreme prejudice, even if that means beating them to death with our entrenching tools!” Command Sergeant Major John Troxell tweeted on Tuesday.

He also tweeted a picture of an entrenching tool.

ISIS needs to understand their two options when facing us: surrender or die! Surrender & we will safeguard to due process. Otherwise we will kill with extreme prejudice, even if that means beating them to death with our entrenching tools!

#SEAC3 #DefeatDaesh #ISIS_SurrenderOrDie pic.twitter.com/unH7Mwk9t1 — CSM John Troxell (@SEAC_Troxell) January 9, 2018

On Facebook, he wrote:

“ISIS needs to understand that the Joint force is on orders to annihilate them. So, they have two options should they decide to come up against the United States, our allies and partners: surrender or die! “If they surrender, we will safeguard them to their detainee facility cell, provide them chow, a cot and due process. HOWEVER, if they choose not to surrender, then we will kill them with extreme prejudice, whether that be through security force assistance, by dropping bombs on them, shooting them in the face, or beating them to death with our entrenching tools. “Regardless, they cannot win, so they need to choose how it’s going to be.”

He also posted a condensed version on his Instagram account.

The tweet and posts attracted widespread attention due to its blunt talk about killing terrorists. The response on social media was overwhelmingly positive, particularly among service members and veterans.

Some responded with criticism, and there was at least one threat to report the comment on Twitter.

However, there was no backing down from Troxell or the Pentagon. A spokesman for the Joint Chiefs of Staff, on which Troxell serves as an adviser to Chairman Marine Gen. Joseph Dunford, did not repudiate his remarks.

“His intent was to communicate the tenacity of the warrior ethos that, even when faced with the brutal and unforgiving nature of combat, will use every resource available to fight and win,” Air Force Col. Pat Ryder said in a statement to the Washington Post.

Troxell’s comments align with the Pentagon’s stance on ISIS. Defense Secretary Jim Mattis, who has warned ISIS to surrender or face annihilation.