Yahoo TV

The FBI on Wednesday said it has not detected any explosive devices after several historically Black colleges and universities across the U.S. reported receiving bomb threats earlier this week – forcing many to cancel classes or put their campuses on lockdown.

The threats in cities from Baltimore to New Orleans coincided with the first day of Black History Month, and came as racial tensions remain high over key issues like voting rights and police killings of Black Americans.

Lopez Matthews, Jr. is a librarian at Howard University in Washington, D.C., which was among those that received threats.

“Whenever African Americans begin to push for rights, push for recognition, our institutions have been targeted by those who seek to silence our voices. So they attack our neighborhoods, they attack our schools, they attack our churches...."

Edward Waters University in Florida, Morgan State University in Maryland, Spelman College in Georgia and Xavier University of Louisiana also received bomb threats.

White House press secretary Jen Psaki earlier this week pledged that the administration was taking the threats “incredibly seriously."

"I will say that these are certainly disturbing and the White House is in touch with inter-agency partners, including federal law enforcement leadership on this.”

The U.S. intelligence community warned months ago that racially motivated violent extremists, such as white supremacists, would potentially seek to carry out mass-casualty attacks on civilians.

Some of these schools have been targeted before.

Howard University came under threat from racist attackers in 1919, and again in the 1960s during the U.S. civil rights movement.

Lopez Matthews hopes that history helps give many on campus a much-needed resiliency.

"You have to continue to go on about your day, go on about your life. You just go on with a heightened sense of urgency, a heightened sense of, 'Let me be aware of my surroundings,' just to protect yourself and protect the school."

The FBI said its Joint Terrorism Task Forces are leading an ongoing investigation, and that the threats are being investigated as racially or ethnically motivated violent extremism and hate crimes.