SAO PAULO (Reuters) -Boeing Co’s 737 MAX plane on Wednesday quietly restarted commercial flights in Brazil, the first country in the world to do so, 20 months after the aircraft was grounded worldwide by regulators following two deadly crashes that killed hundreds. The flights are being operated by Gol Linhas Aereas Inteligentes, Brazil’s largest airlines and one of Boeing’s biggest customers. The first flight took place between the Brazilian cities of Sao Paulo and Porto Alegre, according to data from FlightRadar24. On Wednesday, the flights restarted with little fanfare. Gol declined to provide advanced information on the routes and flights on which it would use the MAX and also did not post an announcement on its homepage to inform clients that the MAX Is flying again. A Gol spokesman declined to comment on how the inaugural flight went. The flights are a key milestone for Boeing as well, which had been trying to get the planes back in service much earlier, missing its initial target of late 2019. The MAX is its latest version of its bestselling 737 family of narrow-body jets. Boeing also declined to comment on Gol’s inaugural flight. The aircraft was greenlit in late November by Brazil’s civil aviation regulator ANAC in November, following a similar decision by the U.S. Federal Aviation Administration. American Airlines is expected to be the next operator to restart flights with the MAX on Dec. 29.