Amy Kellogg reported the latest details this morning after a gruesome terror attack outside a factory in France.

Attackers carrying ISIS flags brought a decapitated person to the location in the northwest town of Grenoble. The severed head of the victim, with Arabic phrases affixed to it, was placed on a fence. 

The victim was reportedly carjacked by the terrorists, then beheaded.

Gas cannisters then exploded at the scene, starting a fire that was put out by authorities.

One suspect is in custody, while a second was killed in a firefight with authorities. 

Kellogg reported several suspected accomplices are being held and others are being sought.

The industrial gas factory is operated by Air Products, a company based in Allentown, Pa.

 

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A local official confirmed the nation is on high alert.

"The terrorism threat is at a maximum," Alain Juppe, mayor of Bordeaux, told Fox News.

One man, who authorities said was an extremist known to authorities was under arrest following the attack. There were unconfirmed reports the other was killed.

The attack came months after well-known ISIS social media accounts and propaganda video threatened attacks in the U.S., Belgium and France.

"We advise you that we will come to you with car bombs and explosive charges and we will cut off you heads," stated one such threat that mirrored Friday morning's attack.

Sky News, citing French legal sources, reported that the severed head had Arabic writing scrawled across it and was placed on a fence next to an Islamist flag.

French authorities tell Fox News that approximately 10 people were injured. A local police deputy described the attack as "definitely" a terrorist act. France's Interior Minister Bernard Cazenueve was on his way to the scene.