URBANA, Ill. (AP) — The University of Illinois is ramping up enforcement of restrictions on student activity after more than 330 COVID-19 cases in two days on the school’s Urbana-Champaign campus.

In an email to students, Chancellor Robert Jones said he expects all undergraduates to “limit their in-person interactions to only the most essential activities” for the next two weeks starting Wednesday evening. He said those activities include taking twice weekly COVID-19 tests, attending class and purchasing groceries.

Since students returned to campus Aug. 16, more than 1,000 people on campus have tested positive.

Meanwhile, Illinois State University in Normal is reporting about 1,025 students have tested positive since the start of the fall semester two weeks ago.