In 1947, General Võ Nguyên Giáp retreated his command to Tan Trao deep in the hills of Tuyên Quang Province. The French sent military expeditions to attack his bases, but Giap refused to meet them head-on in battle. Wherever the French troops went, the Viet Minh disappeared. Late in the year the French launched Operation Lea to take out the Viet Minh communications center at Bắc Kạn. They failed to capture Ho Chi Minh and his key lieutenants as intended, but 9,000 Viet Minh soldiers were killed during the campaign which was a major blow for the insurgency.