were executed as spies, either summarily or after military commissions. After World War II From 1948 to 1960, the Malayan Communists committed numerous effective acts of sabotage against the British Colonial authorities, first targeting railway bridges, then hitting larger targets such as military camps. Most of their efforts were intended to weaken Malaysia's colonial economy and involved sabotage against trains, rubber trees, water pipes, and electric lines. The Communists' sabotage efforts were so successful that they caused backlash among the Malaysian population, who gradually withdrew support for the Communist movement as their livelihoods became threatened. In Mandatory Palestine from 1945 to 1948, Jewish groups opposed British control. Though that control was to end according to the United Nations Partition Plan for Palestine in 1948, the groups used sabotage as an opposition tactic. The Haganah focused their efforts on camps used by the British to hold refugees, and radar installations that could be used to detect illegal immigrant ships. The Stern Gang and the Irgun used terrorism and sabotage against the British government and against lines of communications. In November 1946, the Irgun and Stern Gang attacked a railroad twenty-one times in a three-week period, eventually causing shell-shocked Arab railway workers to strike. The 6th Airborne Division was called in to provide security as a means of ending the strike. In Vietnam The Viet Cong used swimmer saboteurs often and effectively during the Vietnam War. Between 1969 and 1970, swimmer saboteurs sunk, destroyed, or damaged 77 assets of the U.S. and its allies. Viet Cong swimmers were poorly equipped but well-trained and resourceful. The swimmers provided a low-cost/low-risk option with high payoff; possible loss to the country for failure compared to the possible gains from a successful mission led to the obvious conclusion the swimmer saboteurs were a good idea. During the Cold War On 1 January 1984, the Cuscatlan bridge over the Lempa river in El Salvador, critical to the flow of commercial and military traffic, was destroyed by guerrilla forces using explosives after using mortar fire to "scatter" the bridge's guards, causing an estimated $3.7 million in required repairs, and considerably impacting on El Salvadoran business and security. In 1982 in Honduras, a group of nine Salvadorans and Nicaraguans destroyed a main electrical power station, leaving the capital city Tegucigalpa without power for three days. As crime Some criminals have engaged in acts of sabotage for reasons of extortion.