Even before Jajce fell, the ABiH appears to have been planning some sort of offensive against the Bosnian Croats in central Bosnia. After October 29, 1992, the increasing numbers of able-bodied military-age Muslim refugees entering the region were organized, armed, and trained for offensive operations; mujahideen, ABiH soldiers, and armed refugees were infiltrated into key villages in groups of three or four men and hidden in Muslim homes or mosques; and by the end of 1992, the ABiH had positioned a number of its combat brigades in key locations throughout the Lasva, Kozica, and Lepenica Valleys.1 In retrospect, the latter actions were particularly significant.
The first phase of the ABiH offensive plan began on January 20–21, 1993, and took the form of a probing action designed to seize key terrain and position forces for the coming main attack; to test HVO resistance and uncover HVO defensive plans and methods; and probably to test the reactions of UNPROFOR forces to an open conflict between the Muslims and Croats. This stage of the campaign, which was preceded by an ABiH III Corps attack on the town of Gornji Vakuf in an attempt to seal off the central Bosnia battlefield by closing the vital Route DIAMOND supply route, lasted only a few days, in large part because the HVO was able to repulse the main Muslim probes and quickly force a stalemate. The ABiH subsequently drew back and reformed in preparation for the main offensive in mid-April, 1993. The ABiH planners probably viewed the UNPROFOR’s lack of response as a “green light” for the planned main attack in April.
The ABiH achieved tactical surprise with its January probing operations. Brigadier Ivica Zeko, the OZCB intelligence officer at the time, said in retrospect that it is clear the Muslims were positioning their units for an offensive, but that neither he nor anyone else in the HVO had a clear indication of it before the Muslims launched their attack.2 The HVO was working with the Muslims against the Serbs, and no one was looking for Muslim perfidy. For example, the HVO headquarters in central Bosnia apparently did not target the ABiH for intelligence purposes before mid-January, 1993, although the Muslim intelligence services targeted the HVO.3 But even had the HVO known in advance of the Muslim attack, there is little that could have done in terms of repositioning its forces, which were heavily committed on the lines against the Serbs.
Despite Zeko’s disclaimer, the OZCB apparently did have some indications that something was about to happen. The attack on Gornji Vakuf and