A Metropolitan Police Department car drives through the snow on Capitol Hill in Washington, U.S., January 25, 2021.
A Metropolitan Police Department car drives through the snow on Capitol Hill in Washington, U.S., January 25, 2021. Reuters / ALEXANDER DRAGO

A 16-year-old boy was arrested on Thursday and charged with calling in bomb threats at seven predominantly Black schools in Washington a day earlier, the city police department said.

The four high schools and three charter schools, which were evacuated following Wednesday's bomb threats and later cleared, included Dunbar High School, which was threatened on Tuesday during a visit by U.S. Vice President Kamala Harris' husband.

The teenager from Southeast Washington was charged with making "terrorist threats," the Metropolitan Police Department posted on Twitter. Authorities did not release the suspect's name and said the investigation into the incident was continuing.

Authorities have not indicated a connection to race in the spate of bomb threats, and police said Tuesday's incident did not appear to be targeted at Harris' husband, Douglas Emhoff, who was visiting Dunbar for a Black History Month event.

But the incidents have further raised fears among Black communities already rattled by a series of bomb threats made last week against at least a dozen historically Black colleges and universities, or HBCUs, nationwide.

No explosives were found at any of the HBCUs, but the threats are being probed by the FBI.

The United States faces heightened threats from extremist groups, underscored by the bomb threats at many HBCUs, among other factors, the Department of Homeland Security said on Monday.