Thursday marked the deadline for cities and states submitting bids to land Amazon.com Inc.'s new headquarters.

In Missouri, officials pitched a statewide headquarters spread across three cities and connected by a futuristic transportation concept called Hyperloop.

In New Jersey, combined incentives by Newark and the state could total nearly $7 billion.

But in Indianapolis? Who knows. The bid is secret.

"Given the nature of economic development projects such as this, the information within Indy’s regional bid will remain confidential to respect Amazon’s process and the information within it," Indy Chamber spokesman Joe Pellman said in a written statement.

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The chamber is spearheading Central Indiana's bid, with Fishers Mayor Scott Fadness and Indianapolis Mayor Joe Hogsett in support. The chamber sent its bid to Amazon on Tuesday, Pellman said.

What we do know about the bid is fairly minor. In deciding what form the proposal would take, officials opted to choose a six-page "microsite" that provides a three-dimensional, interactive experience for those viewing the details, Hogsett told IndyStar this past week.

Hogsett also acknowledged that landing the Seattle-based company's second headquarters is a "long shot," but one worth pursuing with the collaboration of other local leaders.

"It's too big of a project to not bid on," Hogsett said. "I hope that when all is said and done, we'll be in the fight.

Amazon's new headquarters, called HQ2 by those following every update, could bring as many as 50,000 jobs to whichever region is awarded the bid, as well as billions of dollars in construction spending and investment in surrounding communities.

Indianapolis isn't the only city in the Hoosier state to pursue Amazon. Gary also has expressed interest, even purchasing a full-page advertisement in The New York Times.

Amazon is expected to make a decision next year, but it's unclear how or exactly when. Dozens of cities and states have expressed interest.

Call IndyStar reporter James Briggs at (317) 444-6307. Follow him on Twitter: @JamesEBriggs.

Call IndyStar reporter Ryan Martin at (317) 444-6294. Follow him on Facebook and on Twitter: @ryanmartin.

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