The takeover is latest chapter in standoff between the Arce government and supporters of ex-president Evo Morales.
Regional organisations mobilised behind Bolivian government after troops and armoured vehicles gathered in the capital.
Morales criticised the removal of former President Pedro Castillo, who tried to dissolve Peru’s Congress last month.
Protesters in farming hub of Santa Cruz province block highways as calls grow for release of Luis Fernando Camacho.