The Department of Homeland Security quickly denied claims on Friday from a watchdog group that the Islamic State of Iraq and al-Sham (ISIS) has militants stationed in Juarez, Mexico who plan an 'imminent' attack against the United States.

A DHS spokesman was bewildered, telling MailOnline that 'we are aware of absolutely nothing credible to substantiate this claim' made by Judicial Watch, a center-right group.

'In Mexico?' the official said on the phone. 'I haven't seen that at all.'

An hour before Judicial Watch's report surfaced, Homeland Security Secretary Jeh Johnson said publicly that his agency and the FBI 'are unaware of any specific, credible threat to the U.S. homeland' from the terror network.

And during a late-morning media briefing, White House Press Secretary Josh Earnest said flatly that 'the most detailed intelligence assessment that I can offer from here is that there is no evidence or indication right now that [ISIS] is actively plotting to attack the United States homeland. That’s true right now.'

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Judicial Watch President Tom Fitton, shown this week in an unrelated TV interview, said his organization had credible information suggesting that the terror group ISIS is planning car-bomb attacks in the US

'Unaware of any specific, credible threat': Homeland Security Secretary Jeh Johnson said Friday that the US doesn't have any intelligence supporting an ISIS-threat theory, but Fitton insisted 'you could drive a truck bomb through' loopholes in his denial

But Judicial Watch president Tom Fitton said in an interview that his sources were 'golden' and called the government's insistence 'so dishonest.'

'It's a non-denial denial,' he told MailOnline.

Citing Johnson's use of words like 'credible' and 'specific,' Fitton said, 'You could drive a truck bomb through that loophole. DHS has not denied our story.'

Judicial Watch reported Friday, based on sources that it would not identify to MailOnline out of concern for their safety, that ISIS terrorists are ' planning to attack the United States with car bombs or other vehicle born [sic] improvised explosive devices.'

The group said a 'warning bulletin for an imminent terrorist attack' had been issued to 'agents across a number of Homeland Security, Justice and Defense agencies,'instructing them 'to aggressively work all possible leads and sources' to prevent it.

It also claimed the commander of Fort Bliss, a U.S. Army base near the Juarez border crossing, has been briefed on the threat.

'This is dire,' Fitton said. 'Look, this needs to be – It's impossible for me to overstate the seriousness of the threat.'

'The president calls ISIS a Jayvee terror organization, and now we have a report they're in Juarez, planning attacks with al-Qaeda.'

Fitton predicted that the federal government may be playing a stalling game, with the anniversary of the 9/11 terror attacks approaching in less than two weeks.

'This may be a case of them saying two weeks from now that they took care of the threat the Judicial Watch was saying [was there],' he said.

Later in the afternoon the Fox News Channel and Breitbart.com both published stories about a situation report distributed to law enforcement agencies by the Texas Department of Public Safety.

Fox didn't respond to questions about whether the documents were the same, but a Breitbart reporter said they were.

Fitton said Judicial Watch did not base its reporting on the same bulletin they cited.

Map: The Department of Homeland Security quickly denied claims on Friday from a watchdog group that the Islamic State of Iraq and al-Sham (ISIS) has militants stationed in Juarez, Mexico

ISIS, a fearsome and deadly terror group that dominates much of Iraq and Syria, now includes some militants with passports from the US and other Western nations, a fact that worries American intelligence agencies

Nope: White House Press Secretary Josh Earnest said US intelligence services have 'no evidence or indication right now that [ISIS] is actively plotting to attack the United States homeland'

'The Texas bulletin is not inconsistent with our information,' he said, but 'our story highlights more specific and imminent warnings.'

'It would not surprise us if it turns out the Texas bulletin is a watered-down-for-public-consumption-version of what our sources report.'

Fox News described a 'three-page bulletin, entitled "ISIS Interest on the US Southwest Border".'

'Social media account holders believed to be ISIS militants and propagandists have called for unspecified border operations,' the bulletin read, according to Fox, 'or they have sought to raise awareness that illegal entry through Mexico is a viable option.'

Breitbart had published its own report two hours earlier, reproducing a portion of one page.

That page showed a recent video stunt in which conservative filmmaker James O'Keefe demonstrated the ease with which a terrorist could cross the Rio Grande River by donning an Osama bin Laden mask and wading from Mexico into Texas.

Neither news outlet claimed the law enforcement bulletin articulated any warnings about an imminent terror attack.

Cuidad Juarez: The crime-ridden Mexican border town opposite El Paso, Texas has become a staging ground for illegal immigrants – including drug cartel members and narcotics smugglers – to enter the US illegally

Judicial Watch claimed the commander of Fort Bliss, an Army base in Texas, has been briefed on

But Fitton stuck to his guns, insisting that the threat of an ISIS incursion into Texas – Juarez abuts El Paso with just the Rio Grande in between – is real.

'We take it seriously,' he said. 'We didn't put it out there lightly.'

In a nod to his organization's frequent alarms about border security in America's southwest, he suggested that if the Obama administration was waving reporters away from the story, it was in order to draw attention away from illegal immigration concerns.

'I can't say who in Washington knows about this,' Fitton said. 'But to be sure, this is exactly the type of information that this administration would have an interest in minimizing, downplaying and withholding, to distract from the disaster on the border and the national security threat there.'

Earnest, President Barack Obama's chief spokesman, told reporters on Friday that America's border crisis is over 'for now.'