Military spokesperson Major General Waheed Arshad said 20 kilometers of fencing in North Waziristan's Lwara Mundi area had been completed.
Islamabad has said it plans to erect a fence along 35 kilometers of its porous 2,500 kilometer border to prevent Taliban militants from crossing between the two countries.
In April, Afghan and Pakistani troops clashed in a border area when Afghan troops tore down part of the fence being erected there.
Afghanistan, which has never recognized the border, opposes the fence.
RFE/RL Afghanistan Report
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