Article R1424-47 of the French General Code of Local Authorities
The fire and rescue services may only intervene outside the boundaries of their department by decision: 1° Of the prefect of their department, in particular in application of an interdepartmental agreement; 2° Of the prefect of their defence and security zone in application of articles L. 742-3 and L. 742-4 of the internal security code; 3° Of the minister in charge of civil security in application of article L. 742-6…