Not having sufficient materiel for two sieges, he laid siege to San Sebastian only, and blockaded Pampeluna.
The others were blockaded in Cadiz.
Buenos Aires was in 1838 blockaded by a French fleet; but Rosas stood firm.
Here he was besieged by Don Frederick of Toledo, Alva's natural son, who blockaded all approach to the town.
Buenos Aires was blockaded by the combined English and French fleets, September 1845, which landed a force to open the passage up the Parana to Paraguay, which had been declared closed to foreigners by Rosas.