The ships were based on the contemporary G-class destroyers building for the British Royal Navy, with some modifications to suit Argentine requirements.

After World War II these ships were modified by installing two single hand-worked 40 mm (1.6 in) Bofors guns between the funnels replacing the original anti-aircraft machine guns, and two twin air-cooled Bofors unique to the Argentine and Swedish navies (instead of the more common water-cooled mounts) replacing the after bank of torpedo tubes.

Radar and sonar were also fitted at this time and Santa Cruz landed the "B" gun in favor of a pair of Hedgehog anti-submarine weapons.

The destroyers' fire kept at bay a group of armed civilians and soldiers attempting to storm the local naval base.

The destroyer force also shelled the headquarters of the Army Antiaircraft School, north of the city, some hours later.