Story highlights Twitter is banning sexually explicit content on its Vine social-video tool

The year-old Vine allows users to post 6-second videos

Anyone who violates the new rules will have their account suspended

Twitter has officially banned pornographic content on Vine, its year-old social-video service. The company announced the changes to its rules and terms of service on Thursday and will begin enforcing them immediately.

Just days after Vine's official launch in January of last year, reports surfaced about the presence of porn on Vine , a service for sharing 6-second long videos on Twitter and with other Vine users. It quickly became a popular spot for short clips of sexually explicit content, some posted by well-known porn stars.

For the past year, there have been no official rules against pornographic videos, though the company worked to keep them out of the public eye by suppressing them in highly visible places like its Editor's Picks and most popular lists. It did raise the minimum age for using Vine from 12 years old to 17 years old. The new rating in Apple's App Store meant Vine carried a disclaimer that warned of "frequent/intense sexual content or nudity."

After the initial flurry of concern, the dark corner of Vine was mostly forgotten about by people who weren't actively seeking out salacious content, at least until last month , when a young man rose to temporary Internet fame when he filmed himself being intimate with a Pop Tart and then a Hot Pocket. He posted the videos to Vine, though they were quickly taken down.

The timing is likely a coincidence. Twitter said the change in policy is just a matter of the type of content that fits with the Vine community.

"As we've watched the community and your creativity grow and evolve, we've found that there's a very small percentage of videos that are not a good fit for our community," the company said in a post announcing the new rules

The new rules forbid videos of sex acts, whether they're alone, with other people or with objects. Sexually explicit animations and nudity are also forbidden. However, Twitter is not blocking all nudity. It makes exceptions for any nudity that is documentary, artistic or educational. For example, breastfeeding photos will still be allowed, as will shots of "nude protesters." Sexually suggestive content is also still welcome, as long as it's clothed.

Twitter is not assembling a full-time Vine porn enforcement task force. The content will largely be flagged by other Vine members using the "Report this post" option. Anyone who violates the new rules will have their account suspended until they delete the offending Vine. Repeat posters might have their account permanently suspended.

Twitter will contact the users who have already uploaded large volumes of naughty Vines and ask them to remove the old content.

"We're notifying users who have posted explicit sexual content in the past that they have a period to either take down or download their existing content using a new tool we've created," a Twitter spokesperson said. That tool is only available for past porn posters for now.