hostilities the Portuguese had only two infantry companies in Guinea Bissau and these concentrated in the main towns, giving the insurgents free rein in the countryside. The PAIGC blew up bridges, cut telegraph lines, destroyed sections of the highways, established arms caches and hideouts, and destroyed Fula villages and minor administrative posts. In late 1962 the Portuguese launched an offensive and evicted the PAIGC cadres that had not integrated with the local population. Open hostilities broke out in January 1963. Belligerents and forces Liberation/PAIGC forces Guinea-Bissau's liberation movement was led and dominated by PAIGC, which was led by Cabral until his assassination in January 1973. By the early 1970s, PAIGC had the support of a majority of the Guinean population, but its combat strength was estimated at no more than 7,000. However, the movement was "well trained, well led, and well equipped", and its guerrilla campaign benefitted both from the terrain – its forces operated primarily from Guinea's dense jungles – and from external support. Organisation In 1964, PAIGC held its Cassaca Congress, which decided on reforms to discourage militarism inside the organisation. Thereafter the war effort was carried out not by autonomous guerrilla groups, but by guerrilla units within a nationwide army, the Revolutionary Armed Forces of the People (Forças Armadas Revolucionárias do Povo, FARP). From then until the close of the war, the basic fighting unit in FARP was the highly flexible "double group" (bi-grupo), which comprised two distinct commandos of 15 to 25 men each, normally operating together but also capable of remaining operational if separated (or if joined with other double groups). Also from 1964, PAIGC implemented what Chabal calls a "dual command" at all levels of its military apparatus: at every level, leadership was exercised jointly by two men, one military commander and one political commissar. External support Senegalese President Léopold Sédar Senghor was generally pro-Western and he cooperated closely with Portuguese leaders in attempting to broker a political solution to the conflict. (Brazil, itself a former Portuguese colony, also offered to mediate.) At the same time, however, Senegal provided safe haven to PAIGC from 1966, when Senghor's government formally agreed to allow PAIGC soldiers free movement in and out of Senegal, where PAIGC would be allowed to establish bases. Simultaneously, PAIGC retained its headquarters-in-exile in Guinea-Conakry, Guinea's other neighbour and a continued ally of PAIGC. Elsewhere in Africa, PAIGC received material support from Libya,