Passage: While the 1967 insurgency had been unplanned, the Khmer Rouge tried, without much success, to organize a more serious revolt during the following year. The prince's decimation of the Prachea Chon and the urban communists had, however, cleared the field of competition for Saloth Sar (also known as Pol Pot), Ieng Sary, and Son Sen—the Maoist leadership of the maquisards. They led their followers into the highlands of the northeast and into the lands of the Khmer Loeu, a primitive people who were hostile to both the lowland Khmers and the central government. For the Khmer Rouge, who still lacked assistance from the North Vietnamese, it was a period of regroupment, organization, and training. Hanoi basically ignored its Chinese-sponsored allies, and the indifference of their "fraternal comrades" to their insurgency between 1967 and 1969 would make an indelible impression on the Khmer Rouge leadership.On 17 January 1968, the Khmer Rouge launched their first offensive. It was aimed more at gathering weapons and spreading propaganda than in seizing territory since, at that time, the adherents of the insurgency numbered no more than 4–5,000. During the same month, the communists established the Revolutionary Army of Kampuchea as the military wing of the party. As early as the end of the Battambang revolt, Sihanouk had begun to reevaluate his relationship with the communists. His earlier agreement with the Chinese had availed him nothing. They had not only failed to restrain the North Vietnamese, but they had actually involved themselves (through the Khmer Rouge) in active subversion within his country.

Question: What year the did the insurgency occur?
1967