COLUMBIA (AP) – A University of Missouri professor who challenged his students to show up for class despite fears over racially-motivated threats of violence or risk missing an exam says he has offered his resignation.

Dale Brigham told The Associated Press by email Wednesday that he ultimately backtracked and told students they could take the exam on a later date. His initial email to his Nutritional Science 1034 class urging them to “not give in to bullies” and warning that the test would be administered Wednesday whether students showed up or not sparked an angry response.

Brigham says he has offered his resignation, although university spokesman Christian Basi said he didn’t know yet whether the school had accepted the resignation.

A student at another campus is accused of having made the online threats.