 In 1962 Venezuela had announced that it was rejecting the 1899 boundary and would renew its claim to all of Guyana west of the Essequibo River.In 1966, Venezuela seized the Guyanese half of Ankoko Island, in the Cuyuni River, and two years later claimed a strip of sea along Guyana's western coast.Another challenge to the newly independent government came at the beginning of January 1969, with the Rupununi Uprising.