evidence: A border feud has been spiraling over the Essequibo region, which has been administered and controlled by Guyana for more than a century, although Venezuela also claims the disputed area. Venezuela recently conducted a referendum, which it claims citizens supported, that aims to give Venezuela authority over the Essequibo region. Guyanese officials said in response that the country is preparing to defend itself and its borders in case of an invasion. [...] The long-running dispute over the Essequibo —which comprises some two-thirds of Guyanese territory— has intensified since ExxonMobil discovered oil there in 2015. [...] Guyana, a former British and Dutch colony, insists the Essequibo frontiers were determined by an arbitration panel in 1899. But Venezuela claims the Essequibo River to the region's east forms a natural border recognized as far back as 1777.