On April 25, 1965 there was a rebellion against the government of the Dominican Republic by a small portion of the military and a number of political parties, to include the communists, although the movement was not dominated by communists. The rebellion called on the government to restore the 1963 constitution and its duly elected president, Juan Bosch. The majority of the military stayed loyal to the status quo government which had forced Bosch from office after only serving a year of his presidential term.

The Constitutionalist forces swept the government forces from the heart of the city except for in the north. Otherwise they controlled everything west of the Ozama river, while the loyalists controlled everything east of the river. In the process, the rebels captured much equipment including about a dozen tanks of at least two types, AMX-13s and Landsverk L-60 light tanks. With a larger number of tanks, artillery and aircraft the loyalist forces counter-attacked trying to retake the city. However, after three days of intense fighting they were rebuffed with heavy losses on both sides. It is not clear whether or not the Constitutionalists were poised on the brink of victory, but because of the communist influence, the United States intervened to prevent a second Cuba.

The American marines and paratroopers moved into Santo Domingo unopposed and drove a wedge between the loyalists and the rebels. Ostensibly this was to separate the two sides, but in effect it ended up favouring the loyalists as it effectively split the constitutionalist forces in two, something the Loyalists did not waste time taking advantage of to retake the northern sector of the city. Sporadic attacks were made against the U.S. troops, sniper fire and small raids. However, in general the Constitutionalists were overawed by U.S. military might and settled down to wait for the outcome of the U.S. brokered settlement.

The Consitutionalists organized their forces into basic military units called "commandos". The commandos were organized along party, labour union and trade association lines and given geographic areas to defend. The commandos were backed up by other commandos designated as mobile units. These generally were equipped with an assortment of jeeps and small trucks.

The mission of the commandos was to reinforced weak points during combat, conduct quick attacks, and to patrol the Constitutionalist zone. Their general commander was a member of the Communist 14th of June movement, Rafael "Baby" Mejia. They were formed on the initiative of the Military Bureau of the 14th of June movement and began to operate in the northern zone on April 25th. As the fighting continued and intensified mobile units were created to operate throughout the Constitutionalist zone.

One of the principal weapons of the mobile units was a truck or jeep mounted medium or heavy machine-gun. For the most part these were air or water cooled .30 and .50 caliber machine-guns U.S. Second World War design. It was soon found that the trucks drew a lot of fire, so steps were taken to protect them. Sandbags were used to line the beds where the machine-guns were mounted, both as a protection measure and as a means of weighing down the automatic weapon to make it more stable when fired. The trucks were often painted with the name of the commando unit to which they belonged and sometimes given personal names. More elaborate protection was made in some cases when the beds where the machine-guns were mounted were completely encased in steel plates. The driving compartments were generally not armoured or very lightly armoured. This would seem to indicate that the intention of the armor was to back up into battle to provide an instant pill box, or protected base of covering fire. Photos show that at least three vehicles were so armoured, one Toyota Land Cruiser and two M151 jeeps.

How these vehicles were individually used is not known, but since the mobile units were in the thick of the heaviest fighting, it can be assumed that they were backed up roads and alley ways to fire at particular difficult enemy positions. Their armor protected them from incoming infantry fire, and their mobility allowed them to fire and withdraw before the enemy could bring his heavy weapons to bear. After the arrival of U.S. forces, the marines were harassed by just such a vehicle. "Tiro Alegre" (Happy Shot) the name of a machine-gun truck (may or may not have been armoured) would sneak out, drive like mad and loose off a belt of ammunition at the marines and withdraw. The gunner of the truck never hit much, and the marines were never able to bring to bear their heavy weapons even though they tried on numerous occasions.

Insurgent Armor in Latin America

Insurgent Armor: Introduction
Insurgent Armor: Costa Rica 1948
Insurgent Armor: Cuba 1958
Insurgent Armor: Dominican Republic 1965
Insurgent Armor: Chile 1973
Insurgent Armor: Nicaragua 1978-1979
Insurgent Armor: El Salvador 1981-1989
Insurgent Armor: Colombia 1993-1998