SILVER SPRING, Md. -- A Montgomery County high school has been given the all-clear after students were evacuated following a bomb threat, according to the school’s principal.

Montgomery Blair High School Principal Renay Johnson said via Twitter around 1:15 p.m. Thursday that the building had been evacuated due to a bomb threat.

Authorities were at the scene to investigate. Students were dismissed for the day and the school was cleared shortly before 3 p.m., Johnson said.

All evening activities, with the exception of a concert, have been canceled, Johnson said.

No further details were immediately available.

Stay with WUSA9 for more on this developing story.