Twitter has announced it is to close its video sharing service Vine about four years after it launched.
Vine let people share six-second-long video clips that played on a loop.
Twitter did not give a reason for the closure, but earlier on Thursday it announced it was cutting 9% of its workforce following slow growth of the social network.
"In the coming months we'll be discontinuing the [Vine] mobile app," the company said in a blog.
On learning of the move, Rus Yusupov - one of the three co-founders of Vine - tweeted: "Don't sell your company!"
Warned of change
Twitter acquired Vine before it had officially launched in 2012 for a reported $30m (£24.6m).
But it has since integrated a separate video facility into Twitter's main platform, and acquired and launched the livestreaming app Periscope.
"Nothing is happening to the apps, website or your Vines today," the blog added.
"You'll be able to access and download your Vines. We'll be keeping the website online because we think it's important to still be able to watch all the incredible Vines that have been made."
It added that users would be notified before it made any changes to the Vine app or website.
"Twitter was all about setting a constraint on communication - 140 characters - and with Vine it tried to do the same to video," said Ian Fogg, an analyst at the tech consultancy IHS Markit.
"The problem is that Vine didn't keep pace with the innovation from Snapchat, Facebook and other players in the market."
Analysis: Dave Lee, North America technology reporter
Vine seemed a natural progression for Twitter when it was launched in 2013.
Six-second videos seemed a great pairing for a service famed for its punchy 140-character posts.
But in time, it was clear Vine just couldn't compete with short video on Snapchat and Instagram, and that's why Twitter has decided to shut it down.
And with Twitter looking to shed a fair bit of its workforce (again), there really is no justification for a separate app.
What's not clear is whether Twitter plans to integrate Vine-like features into its main app - I'd be very surprised if they binned the format altogether.
Vine has a dedicated fan base, and there are many Vine celebrities out there.
But you're almost as likely to see a Vine re-shared on Facebook than you are to see it on Vine itself - perhaps that was part of the problem.
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