At 15:30, Egyptian forces captured Fort Lahtzanit, the first fortification of the Bar Lev Line to fall, and by then the infantry had been reinforced with 82mm B-10 and 107mm B-11 rifles. At the same time, engineers began operating their water pumps against the sand wall, opening the first passage in less than an hour, and the Egyptians moved up their bridging units to the canal. By 16:30 eight waves had brought across the canal ten infantry brigades in all five bridgeheads, totaling 23,500 men (around 4,700 at each bridgehead). Each bridgehead was on average six kilometers (3¾ mi) wide and around two kilometers deep. The Egyptians had high-velocity 85mm and 100mm rifled anti-tank guns in action on the east bank by that time.