Elon Musk just tweeted that his Boring Company tunnel project has received “verbal [government] approval” to build a hyperloop connecting New York City, Philadelphia, Baltimore, and Washington, DC.

Just received verbal govt approval for The Boring Company to build an underground NY-Phil-Balt-DC Hyperloop. NY-DC in 29 mins. — Elon Musk (@elonmusk) July 20, 2017

While we work to verify his claim, Musk is continuing to tweet more details about the project. The hyperloop, an ultrafast method of travel first developed by Musk in 2013, would only take 29 minutes to travel between New York City and DC, he claims. And it would feature “up to a dozen or more” access points via elevator in each city.

City center to city center in each case, with up to a dozen or more entry/exit elevators in each city — Elon Musk (@elonmusk) July 20, 2017

Musk famously released his hyperloop concept as an open-source white paper in 2013, arguing that he was too busy with his companies Tesla and SpaceX to devote energy to it. Since then, Musk has grown increasingly frustrated with surface-level transportation, as evidenced by his tunnel project dubbed the Boring Company.

The Boring Company started as a joke, but became increasingly serious as Musk began tunneling in a parking lot outside of SpaceX in an effort to demonstrate his ability to dig faster and more efficiently than traditional tunneling projects. Musk says he’s working on tunnel-boring machines than can simultaneously dig up and reinforce tunnels, which could go a long way toward solving a big engineering challenge. He recently announced the completion of the first section of tunnel under Los Angeles.

Since then, he has released a number of photos and concept videos demonstrating how his intricate underground roadway system would actually look. It looked amazing, but irked public transportation advocates for prioritizing individual optimization over system optimization.

As far as what he meant by “verbal govt approval,” we’ve reached out to both the Boring Company and the US Department of Transportation for more information, and we’ll update this post if we hear back. Some are already speculating that Musk may have gotten the sign off from White House senior advisor (and Trump son-in-law) Jared Kushner’s office of American Innovation, which has expressed interest in the hyperloop.

Elon Musk’s tweet sort of syncs w/what Kushner’s Office of American Innovation floated to @emilyjanefox last month https://t.co/B5s63MMVLq pic.twitter.com/KmDWfVNgem — Kia Makarechi (@Kia_Mak) July 20, 2017

Update, July 20th, 11:43AM ET:

Musk is continuing to tweet his thoughts about this (maybe completely insane?) project.

For sure. First set of tunnels are to alleviate greater LA urban congestion. Will start NY-DC in parallel. Then prob LA-SF and a TX loop. — Elon Musk (@elonmusk) July 20, 2017

According to his tweet, work on the New York-to-DC tunnel / hyperloop will happen in parallel to the already-in-progress LA tunnel. And if Texas wants a hyperloop, too, well who is Elon Musk to deny Texas a hyperloop.

Update, July 20th, 12:47AM ET:

In a subsequent tweet, Musk clarified what sort of approval his project has received.

Still a lot of work needed to receive formal approval, but am optimistic that will occur rapidly — Elon Musk (@elonmusk) July 20, 2017

Meanwhile, transit experts sounded a skeptical note about how “rapidly” Musk’s project would get approved.

Approval needed from: Federal DOT; 6 states; 17 counties; numerous cities; hundreds of elected officials. Definitely happening rapidly. https://t.co/QBDoFKLscI — Yonah Freemark (@yfreemark) July 20, 2017

Elon Musk's hyperloop competition in 2016