Islamic terror threat is at its highest in the U.S. since 9/11 attacks with much of the risk coming from people radicalized in the country, according to the House Homeland Security Committee’s December Terror Threat Snapshot released Tuesday.

There have been 227 cases of homegrown terror cases since the tragic event 15 years ago killed almost 3,000 people in series of four coordinated attacks, the report said. Of these, 115 jihadist cases were reported in 2015 and 2016 alone.

“The attack last week at Ohio State University is further proof that our homeland remains in the crosshairs of Islamist terrorists. Groups like ISIS are radicalizing new operatives from within our borders, and just this week their new spokesman called for more inspired attacks by supporters ‘all over the world,’” House Homeland Security chairman Michael McCaul (R-Texas) said in a statement.

This year the Islamic State group, also known as ISIS, carried out 62 attacks across the world, killing 215 people and injuring 732 others in several countries, including the U.S., France and Belgium. This threat to America and Europe remains in 2017 mainly because terrorists have been fleeing Iraqi city Mosul and Syrian Raqqa — both ISIS strongholds, the report noted.

The terrorist group’s shift in spreading messages from urging fighters to join the jihad in Syria and Iraq to carrying out attacks in their home countries is likely to increase radicalization, according to the report. Moreover, terrorists are also using refugee programs, porous borders, and popular migration routes to enter countries throughout the West.

“Make no mistake: we face a deadlier threat than ever before not only because our enemies have gotten savvier, but because we took the pressure off them,” McCaul said.

The terror snapshot also cited the National Counterterrorism Center’s 2015 comment that “…individuals with ties to terrorist groups in Syria are attempting to gain entry to the United States through the U.S. refugee program, which has resettled nearly 13,000 Syrian refugees across the nation this year.”

Furthermore, the Iran nuclear deal along with the volatile situation in Iraq, Syria, and Yemen has placed the Iranian government in a stronger position to get regional hegemony, according to the snapshot.

“Iranian aggression, particularly in the Persian Gulf, has become routine and remains largely unopposed. If left unchecked, Tehran will continue to threaten United States’ interests at home and abroad,” the report noted.