Sept. 11 (UPI) — Six historically black colleges and universities in the South locked down on Thursday morning amid potential threats that various law enforcement agencies are investigating.

Alabama State University, Virginia State University, Hampton University in Virginia, Clark Atlanta University in Georgia and Southern University in Louisiana locked down after receiving possible threats of an unknown nature, ABC News reported.

Spelman College in Atlanta did not receive any threats but locked down out of caution.

Officials at Alabama State said they received “terroristic threats” and locked down the campus.

“We are working in close coordination with the appropriate law enforcement agencies to assess the situation and to ensure the safety and security of our students, faculty, staff and the broader ASU community,” ASU officials told USA Today in a prepared statement.

Officials at Virginia State and Hampton temporarily ceased operations and notified students, faculty and staff to stay at home after receiving possible threats, according to HBCU Buzz.

Virginia State officials shared an email with ABC News that they sent to students, faculty and staff.

The message told them to remain locked down while campus police worked with local, state and federal law enforcement to determine if the threat there is credible.

Other colleges and universities have announced that classes and school-related activities are canceled through the weekend.

No incidents or injuries have been reported after the HBCUs received threats, which has plagued many colleges and universities amid hoaxes and swatting incidents so far this school year.

Several HBCUs in 2022 were among at least 57 colleges and universities that received bomb threats made through phone calls, e-mails, messages and anonymous online posts, according to the FBI.

Thursday’s threats came a day after conservative activistCharlie Kirk was shot and killed during a Wednesday afternoon event at Utah Valley University in Orem.