Hunter Park has been arrested at the University of Missouri campus after death threats were posted online against black students.
Officials linked Hunter Park, 19, to some of the threatening posts but did not say how.
University of Missouri increased security but said there is no “immediate threat”.
Hunter Park’s arrest comes days after University President Tim Wolfe was forced out, accused of not doing enough to address racism on campus.
Threats mostly came from users of the anonymous messaging app Yik Yak.
Yik Yak condemned the threatening messages and said in a news release that the company works alongside authorities to help in investigations and it may share information with law enforcement.
Hunter Park was not on campus or nearby when posting the message, police said.
He lives in Rolla, Missouri, about 100 miles south of the Columbia campus and is a student at the Missouri University of Science & Technology, the school confirmed.
“I’m going to stand my ground tomorrow and shoot every black person I see,” one anonymous post read on Yik Yak.
Another warned black students simply not to come to campus the next day and another said “we’re waiting for you at the parking lots… we will kill you.”
Before the suspect was apprehended, protest leaders said the university administrators were not doing enough to address the threats against minority students.
One black student tweeted an email conversation with his professor in which he told the professor he was scared to come to class because of the threats.
“The only way bullies are defeated is by standing up to them … If we cancel the exam, they win; if we go through with it, they lose,” the professor wrote.
In recent weeks, students staged a sit-in on a university plaza and one graduate student participated in a hunger strike, calling for Tim Wolfe’s resignation.
Tim Wolfe stepped down after the university’s football team joined the cause, threatening not to play until action was taken to address racial issues on the mostly white campus.