WASHINGTON – The Pentagon is sending a "very loud" message to Iran not to harm U.S. troops in the Middle East after intelligence reports revealed a rising level of threats from Iranian paramilitary forces, a senior Defense official said Monday.

The commander of U.S. Central Command, Marine Gen. Kenneth McKenzie, made an urgent request to bolster American forces in the region after observing multiple streams of intelligence that indicated threats to U.S. troops, according to the official who was not authorized to speak publicly. The threats were above and beyond what is usually detected.

There are hundreds of American troops in Iraq and Syria, as well as in surrounding Middle East countries.

The U.S.S. Lincoln aircraft carrier task force and a bomber group were dispatched to send the message to Iran to leave U.S. forces alone, the official said.

The Pentagon also announced Monday that it is bolstering its forces in the Middle East “to counter Iran’s destabilizing activities” and “malign behavior.”

Spokesman Charles Summers said the U.S. military has been prepared to deal with Iranian provocations.

“However, the deployment of the USS Abraham Lincoln Carrier Strike Group and a bomber task force are considered a prudent step in response to indications of heightened Iranian readiness to conduct offensive operations against U.S. forces and our interests,” Summers said. “It ensures we have the forces we need in the region to respond to contingencies and to defend U.S. forces and interests in the region."

That announcement follows a statement released Sunday night by John Bolton, President Trump's national security adviser. Bolton referred to "troubling and escalatory indications and warnings" from Iran as the reason for the deployment of the Lincoln and the bombers.

Sen. Marco Rubio, R-Fla., tweeted Monday that Iran could not escape blame by sending proxy forces to attack U.S. troops. Any attack, he said, would be attributed to Iran and Gen. Qassem Soleimani, who heads the elite Quds Force of Iran's hard-line paramilitary Revolutionary Guard.

"We will not distinguish between attacks from Shia militias in #Iraq & the #IRGC that controls them, Rubio tweeted.

The Pentagon has a history of bad blood with Iranian forces in the region, particularly in Iraq. During the peak of fighting in Iraq, U.S. commanders produced evidence of sophisticated explosives used to kill U.S. troops. Known as explosively formed penetrators, the weapons required expertise and manufacturing that wasn't available to most militants in Iraq.

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