Colonel Enrique del Castillo Bravo who was succeeded by Carabineros Commanders Emeterio Jarillo Orgaz and José Casted Sena.

At the onset of the Civil War del Castillo was Engineer Captain at the Nr 1 Railway Regiment (Regimiento de Ferrocarriles nº 1) at Leganés and was transferred to the Carabineros Corps.

The Chief of Staff was Major Ruiz del Toro and the Comissar Demetrio Martín Martínez.

It specialized in trench warfare and remained in its post until 27 March 1939 when the Madrid defense crumbled.

Militia Captain Juan Borrás Garcerán was named Chief of Staff a few days before the surrender of the Republic that marked the end of the war.