New York to Washington in 29 minutes? Elon Musk says it's possible and he has the government's approval to do it (though it's anyone's guess which government or how long it'd take to build). "Just received verbal govt approval for The Boring Company to build an underground NY-Phil-Balt-DC Hyperloop. NY-DC in 29 mins," the billionaire inventor and entrepreneur tweeted Thursday afternoon. OJ Simpson Faces High-Stakes Nevada Parole Hearing "City center to city center in each case, with up to a dozen or more entry/exit elevators in each city," he said in another tweet. The Boring Company is Musk's tunneling venture. It was not clear which government had given him the approval -- and Musk did not answer multiple tweets from people around the world asking him the same. Sheriff ID's Another Victim of Serial Killer John Wayne Gacy "Still a lot of work needed to receive formal approval, but am optimistic that will occur rapidly," Musk said about an hour later. Representatives of the U.S. Department of Transportation were not immediately available to respond to Musk's assertion; the federal government would presumably have some say over such a venture. Big New SpaceX Rocket Launch Will Be Risky, Musk Says Skeptics wasted no time in challenging Musk on the details, including the BBC's Silicon Valley reporter, who asked whether the CEO was announcing prematurely in a bid to drum up support. "Support would be much appreciated!" he replied. In a later response to an inquisitive follower, Musk did say the work on the New York-to-Washington tunnel would run in parallel to an existing project to build tunnels in Los Angeles. "Then prob LA-SF and a TX loop," he tweeted. He gave no estimate for how long any of these projects would take or what they might cost. Musk is best known for his electric car company Tesla and his space venture SpaceX, as well as co-founding PayPal. The inventor first proposed the Hyperloop electromagnetic tube system in 2013. Earlier this year the California tech company Hyperloop One unveiled a plan for a NY-to-DC system. Musk's system appeared to be different from theirs, though.