Bogota, April 30 (Reporter) An army helicopter crashed and killed all nine soldiers on board when returning from supplying troops in northern Colombia, Colombia's National Army said. The helicopter lost communication with the base in the early afternoon and was later found to have crashed near the municipality of Santa Rosa, Bolivar Department, said the army's statements. Expressing his regret over the tragedy on social media, President of Colombia Gustavo Petro said that troops "were conducting operations against the Gulf Clan." Gulf Clan is known as a criminal ring accused of drug trafficking and murders in Colombia...////...