A new report on the security flaws at the U.S. border confirms President Trump’s claims that terrorists from mostly Middle East criminal networks have hidden among migrants entering the country illegally.

There have been at least 15 confirmed cases of terrorists from groups like ISIS and the Taliban trying to enter the nation, and at least 100 total migrants from nations that harbor terrorist groups have crossed the border since 2001, the year of the 9/11 attacks, according to the report from the Center for Immigration Studies.