Donald Trump wants to know who exactly Harvard’s international students are—and why the countries they hail from aren’t paying up.

Trump claimed the Ivy League university has not been forthcoming about how much of its student body international students make up in an early-morning screed on Sunday.

“Why isn’t Harvard saying that almost 31% of their students are from FOREIGN LANDS, and yet those countries, some not at all friendly to the United States, pay NOTHING toward their student’s [sic] education, nor do they ever intend to,“ Trump wrote.