(0) VANCOUVER, British Columbia, April 08, 2021 (GLOBE NEWSWIRE) -- Calibre Mining Corp. (TSX: CXB; OTCQX: CXBMF) (the "Company" or "Calibre") is pleased to provide an update on the Borosi exploration project held under an earn-in option agreement between Rio Tinto Exploration (LSE:RIO) ("RTX") ("Rio Tinto") and Calibre. Calibre controls a 100% interest in the Borosi concessions located in the prolific Mining Triangle region of northeastern Nicaragua. RTX has the right to earn a 75% interest by spending US$45 million over eleven years in the project (see Calibre news release dated February 24, 2020 (https://calibremining.com/news/calibre-and-rio-tinto-exploration-enter-into-agree-1298/)). The Borosi exploration program is being directed by RTX through a partnership agreement with Calibre as project operator.