Instagram CEO Kevin Systrom says he and co-founder Mike Krieger have resigned from Facebook to "explore our curiosity and creativity again."

It's a major blow to Instagram owner Facebook, as the company continues to lose top executives during a year of scandal and declining community support. Instagram had become something of Facebook's shining star — avoiding the privacy concerns that have plagued the core platform and claiming the youngest users who are increasingly leaving Facebook.

"We're planning on taking some time off to explore our curiosity and creativity again. Building new things requires that we step back, understand what inspires us and match that with what the world needs; that's what we plan to do," Systrom said in a statement.

Several news outlets cited tension with Facebook and CEO Mark Zuckerberg as spurring the resignations. The photo-sharing app has more intensely mimicked the core Facebook service in recent months, introducing a designated tab for long-form video and testing community groups for college students.

The New York Times first reported the departures.

Here's Systrom's full statement on leaving:

Mike and I are grateful for the last eight years at Instagram and six years with the Facebook team. We've grown from 13 people to over a thousand with offices around the world, all while building products used and loved by a community of over one billion. We're now ready for our next chapter. We're planning on taking some time off to explore our curiosity and creativity again. Building new things requires that we step back, understand what inspires us and match that with what the world needs; that's what we plan to do. We remain excited for the future of Instagram and Facebook in the coming years as we transition from leaders to two users in a billion. We look forward to watching what these innovative and extraordinary companies do next.

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