US Secret Service agents rushed Douglas Emhoff, the husband of Vice-President Kamala Harris, to safety on Tuesday while students and administrators evacuated after a bomb threat to a Washington school celebrating a Black History Month event, officials said.

Emhoff was at Dunbar High School, the first high school for Black Americans in the US, according to its website.

A series of bomb threats were made last week to at least a dozen historically Black colleges and universities (HBCUs) nationwide, forcing the institutions to cancel classes and raising fears among Black communities. No explosives were found at any of the locations but the threats are being investigated by the FBI.

The police said that preliminary information indicated Tuesday’s bomb threat was neither related to last week’s threats nor was it targeted at Emhoff. However, it added that a connection with last week’s threats could not be completely ruled out.

The police said that the bomb threat was made in a phone call, which authorities were tracing. The area was deemed safe by late afternoon.