Twitter has blocked searches for the terms “porn” and “sex” on its new video sharing service Vine in an attempt to reduce the level of explicit content being posted. However, the word “gay” and terms relating to “gay” are not blocked despite most of the content being highly explicit.

The new social service owned by Twitter allows users to film and post videos of exactly six seconds in length. They can be shot in stages, allowing users to animate objects or cut between different scenes that are then played in a loop.

Twitter apologised last night for making video of a graphic sex act ‘editor’s pick’- promoting the video to hundreds of thousands of users. The service apologised blaming human error.

Searches for the hashtag ‘#gay’ on the service provides users with countless explicit videos, primarily of men masturbating. The service also suggests users searching for ‘gay’ might also wish to see ‘gayjerk’, ‘gaydick’, ‘gayselfiepose’

In a statement, Twitter said: “Uploaded videos that are reported and determined to violate our guidelines will be removed from the site, and the user account that posted the video may be terminated. ”

Some of the explicit content that PinkNews.co.uk found on the service displayed warnings before users could view the videos.