A man killed himself while detonating explosives after trying to enter Brazil’s Supreme Court, authorities said Wednesday, in an attack on the political heart of the country that prompted the evacuation of court staff and legislators in the capital Brasilia.

The authorities were treating the blasts in Brasília, the capital, as the work of a lone bomber, who was believed to have been the person killed.

Authorities say a man who failed in an attempt to break into Brazil’s Supreme Court has killed himself in explosions outside the building that forced justices and staff to evacuate