On Tuesday, MI5's director general of security service, Ken McCallum, claimed there's been a resurgence of the Islamic terror group known as ISIS.

At the start of his news conference in London, the head of the United Kingdom's domestic spy agency began with a claim that the main concerns to the British homeland are right-wing and Islamic extremists.

"The headline split of our counterterrorist work remains roughly 75% Islamist extremist, 25% extreme right-wing terrorism," McCallum told reporters. "But under that headline, much has shifted. Straightforward labels like Islamist terrorism or extreme right-wing don't fully reflect the dizzying range of beliefs and ideologies we see. We're encountering more volatile would-be terrorists with only a tenuous grasp of the ideologies they profess to follow."

McCallum said that "disinformation," "conspiracy theories," and "online instructional material" have been fueling these two groups.

But what "terrorist trend" concerned him most, the U.K. spy chief added, was the "worsening threat from al Qaeda, and in particular from Islamic State," the group also known as ISIS.

"Today's Islamic State is not the force it was a decade ago, but after a few years of being pinned well back, they've resumed their efforts to export terrorism," he stated. The deadly March concert hall attack in Moscow, he then stated, carried out by offshoot ISIS-K, "was a "brutal demonstration of its capability."

However, according to RT, after detaining several of those involved in the attack, Russian officials said that the terror group Islamic State-Khorasan (ISIS-K) was used as a proxy by Ukraine. Notably, those involved in the attack were reported as fleeing toward the Ukraine border, according to Russian President Vladimir Putin. One of the men captured on video was also seen responding in a Slavic language while being questioned by a Russian soldier. But Kyiv has denied any involvement.

McCallum concluded his press conference with a warning to would-be terrorists, stating that if one takes money from Iran or Russia to carry out terrorist acts in the U.K., "It's a choice you'll regret."

As a note, on Dec. 8, 2016, Iraq war veteran and then-Democrat Rep. Tulsi Gabbard of Hawaii gave a proposal introducing to the House floor the "Stop Arming Terrorists Act" with the proclamation that either the United States or its allies had been funding ISIS.

"Under US law," Gabbard began, "it is illegal for you, me, or any American to provide any type of assistance to al-Qaida, ISIS, or other terrorist groups. If we broke this law, we would be thrown in jail. Yet, the US government has been violating this law for years, directly and indirectly supporting allies and partners of groups like al-Qaida and ISIS with money, weapons, intelligence, and other forms of support in their fight to overthrow the Syrian government."

"This madness must end. We must stop arming terrorists."

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