Ezra Klein is leaving The Washington Post, the paper told staffers in a memo Tuesday. No details yet on who is backing Klein's new venture.

Full memo:

We regret to announce that Ezra Klein, Melissa Bell and Dylan Matthews are leaving The Post for a new venture.

All three were instrumental in two of The Post's most successful digital initiatives, Wonkblog and Know More. We plan to continue building those brands and expanding their reach, and we'll have some exciting announcements related to them in the coming days.

When Ezra joined us in 2009, he was a wunderkind blogger with brash confidence and a burning desire to write a column in the print newspaper. As he leaves us, Ezra is still a brash wunderkind, but now his burning desire has a grander scope: He is looking to start his own news organization, an ambition that befits someone with uncommon gifts of perception and analysis. Ezra’s passion and drive will be missed, but we will take pride in watching him chart out his new venture.

Melissa has played a pivotal role in our digital strategy. As director of platforms, Melissa worked with the embedded developers to introduce WordPress as a secondary CMS, allowing for much of the development experimentation we’ve seen over the last year. She took over blog strategy and worked to hone the number of blogs and strengthen existing brands. She also managed to find time for some writing while here, driving our live coverage expansion, penning a Style column for more than a year, blogging for BlogPost and Style Blog and writing magazine stories. But her biggest strength is her personality, a combination of relentless determination and self-deprecating humor that helped her motivate young developers.

Dylan Matthews is a wunderkind in his own right. A blogger since middle school, Dylan had freelanced for Slate and worked at the American Prospect -- before his 18th birthday. He started contributing to Wonkblog while still a student at Harvard and jumped in full-time in 2012. Last year he launched Know More, which was an instant hit. We will miss his humor and sharp instincts for what works on the Web.

Please join us in wishing Ezra, Melissa and Dylan the best and thanking them for their many contributions to The Post.

Greg Schneider
David Cho
Emilio Garcia-Ruiz

Klein reportedly sought an eight-figure investment for a new venture that would build on Wonkblog, the policy-and-more blog he built for the Post. Post publisher Katharine Weymouth and owner Jeff Bezos declined to supply that money, Ravi Somaiya reported earlier this month. Also in January, Charlie Warzel reported in BuzzFeed that signs pointed to Klein doing a deal with Vox Media.

His new venture joins a suddenly crowded market of startups founded or staffed by journalists with large personal brands:

• Nate Silver decided last year to leave The New York Times for ESPN, which plans to relaunch his FiveThirtyEight.com under its auspices soon.

• Glenn Greenwald left the Guardian last year to join a "a new mass media organization" funded by eBay founder Pierre Omidyar. Dan Froomkin and Jay Rosen also joined the new organization in varying capacities.

• Gawker's Neetzan Zimmerman will be the editor-in-chief of a starting shareup called Whisper.

• Gabriel Snyder, formerly the editor-in-chief of The Wire, will be chief content officer of a mobile news startup called Inside.com.

• Kara Swisher and Walt Mossberg's site AllThingsD announced last year they would part ways with Dow Jones & Co. and relaunched as Re/Code this year. The Wall Street Journal launched a replacement site, WSJD. Both promised live events. Another spinoff from the Journal: The Information, a subscription tech-news site edited by former WSJ reporter Jessica Lessin.

• Proto-blogger Andrew Sullivan left The Daily Beast in early 2013 to relaunch his Daily Dish as an independent, subscription-based publication. Sullivan wrote on Dec. 31 that in its first year, the publication had raised more than $800,000 in subscription revenue and has "almost 34,000 subscribers."

• The New York Times, while obviously not exactly a startup, announced late last year that it would launch "two newsroom startups," including one headed by former Times Washington bureau chief David Leonhardt aimed at the same subject areas as FiveThirtyEight.com.

Writing in Politico, Dylan Byers and Hadas Gold wrote about the Post's decision not to fund Klein. "Even if Bezos could have afforded to give Klein $10 million or more — the Amazon founder bought the paper for $250 million last year — the creation of a separate website was not seen as a wise investment for an organization that, for all its progress in the digital arena, still operates with relative caution."