Authorities warned of lone-wolf terror attacks in U.S. after airstrikes against ISIS

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(CNN) — A U.S. Department of Homeland Security joint intelligence bulletin is warning law enforcement agencies to be on heightened alert for lone-wolf terror attacks on U.S. soil in wake of the airstrikes against ISIS and others in Syria, a U.S. law enforcement official told CNN on Tuesday.

The United States is doing what it must to “take the fight to terrorists,” leading a coalition of Arab nations in a series of airstrikes against the so-called Islamic State terror group in Syria, U.S. President Barack Obama said Tuesday.

At the same time, the United States took action — on its own — against another terrorist organization, the Khorasan Group. Obama described its members as “seasoned al Qaeda operatives in Syria.”

U.S. officials said the group was plotting attacks against the United States and other Western targets.

The plots against the United States were discovered by the intelligence community in the past week, an intelligence source with knowledge of the matter told CNN. The source did not say what the target may have been, but said the plot potentially involved a bomb made of a nonmetallic device like a toothpaste container or clothes dipped in explosive material.

A plot involving concealed bombs on airplanes “was just one option they were looking at,” a U.S. official said.

“Once again, it must be clear to anyone who would plot against America and try to do Americans harm that we will not tolerate safe havens for terrorists who threaten our people,” Obama said in televised remarks from the White House.

The airstrikes in Syria began early Tuesday morning local time. Bahrain, Saudi Arabia, the United Arab Emirates and Jordan took part in airstrikes on ISIS targets, the U.S. military said. Qatar played a supporting role, the U.S. military said.

Noting that he had “made clear that America would act as part of a broad coalition,” the President said: “That’s exactly what we’ve done.”

“The strength of this coalition makes it clear to the world that this is not America’s fight alone,” Obama said at the White House. “Above all, the people and governments in the Middle East are rejecting ISIL and standing up for the peace and security that the people of the region and the world deserve.” ISIL is another acronym referring to the terrorist group, which calls itself the Islamic State.

There is bipartisan support in Congress for the U.S. military actions, Obama said, adding that “America is always stronger when we stand united. And that unity sends a powerful message to the world that we will do what’s necessary to defend our country.”

Strikes came in three waves

The airstrikes “were only the beginning,” Pentagon spokesman, Navy Rear Adm. John Kirby, said. He declined to comment about future military operations.

The airstrikes came in three waves, with coalition partners participating in the latter two, Army Lt. Gen. William Mayville Jr. said Tuesday. The first wave, which mostly targeted the Khorasan Group, started at 3:30 a.m. (8:30 p.m. ET Monday) and involved U.S. ships firing missiles into eastern and northern Syria.

The second wave, 30 minutes later, involved planes striking northern Syria, with targets including ISIS headquarters, training camps and combat vehicles. The third wave, begun shortly after 7 a.m., involved planes targeting ISIS training camps and combat vehicles in eastern Syria, Mayville said.

It’s too early to say what effect the U.S. strikes had against the Khorasan Group, Mayville said.

However, the airstrikes killed the leader of al Qaeda-linked al-Nusra Front, according to a statement released by the group. It identified the leader as Abu Yousef al-Turki, also known as “the Turk.”

The al-Nusra statement posted on Twitter was accompanied by a so-called proof-of-death — a photograph — of the former fighter. CNN cannot independently verify al-Nusra’s claims, but the monitoring group the Syrian Observatory for Human Rights (SOHR) reported the terror group was among those targeted during the airstrikes.

The strikes marked the first time the United States used F-22 Raptor stealth aircraft in a combat role. The military has previously run into problems with the aircraft.

Monitor group estimates at least 70 ISIS militants killed

The airstrikes against ISIS focused primarily on the city of Raqqa, the declared capital of ISIS’ self-proclaimed Islamic State.

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