(CBS News) — For the second day in a row, several historically Black colleges and universities received bomb threats Tuesday, resulting in shelters-in-place and canceled classes as authorities swept campuses looking for devices. No explosions have been reported.

Howard University, in Washington, D.C., was threatened on both days. It declared an all-clear Tuesday as it did Monday.

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CBS Washington, D.C., affiliate WUSA-TV says a bomb threat was also reported at the University of the District of Columbia (UDC) Tuesday.

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Other schools getting threats Tuesday included Edward Waters University in Jacksonville, Florida; Kentucky State University; Fort Valley State, in Georgia; Xavier University in Louisiana; Spelman College in Atlanta and Morgan State in Baltimore.

In addition to Howard on Monday, schools receiving threats included Southern University and A&M College in Baton Rouge, Louisiana; Bethune-Cookman University in Daytona Beach, Florida; Albany State University in Georgia; Bowie State University in Maryland and Delaware State University.

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