ISIS has reportedly struck the U.S. embassy in Baghdad in what could be the furthest incursion yet into Iraq’s capital.

On Tuesday the Islamist militant group took credit for a mortar attack against the embassy in Baghdad. The group bragged about the attack on social media, claiming that there were likely casualties.

“Four rockets strike Green Zone in #Baghdad; helicopters hovering over the Green Zone; ambulances heading that way after strikes!!” one ISIS militant noted on Twitter.

Others noted that the mortars fell short of the U.S. embassy, leaving no one killed or injured.

#Baghdad police: At least 2 mortars fell close to the #US embassy compound. No injuries reported. #Iraq — Rym Momtaz (@RymMomtaz) October 21, 2014

Just one day before the alleged attack, retired Lt. Col. Oliver North claimed that sources in Iraq believed ISIS was planning a “major attack” against the embassy in Baghdad.

“They know Baghdad. They’ve lived in Baghdad,” North said of the militants reportedly planning the attack.

“They are at the gates of Baghdad. They’re coming for us,” he added.

But North’s predictions were also tinged in political criticism, as he used the prediction as a way to attack President Obama and allege a conspiracy to let ISIS take over Iraq for his own benefit.

“I don’t think he gives a d**n,” North said. “I think he’s hoping that he can hold the lid on this until after this election so it won’t be just another disaster for this administration.”

ISIS has been increasing its attacks on Baghdad in recent weeks, including a wave of car bomb and mortar attacks on Sunday that left at least 150 people killed. Four car bombs exploded in Shia districts of Baghdad, leaving 36 people dead and 98 wounded in a span of two hours.

ISIS fighters have been encamped in suburbs surrounding Baghdad and earlier this month sent four mortar shells into the Green Zone, the heavily protected location of the U.S. Embassy and other government buildings.