Image copyright Patty Mayo Image caption Bounty hunter Patty Mayo's channel has had multiple videos taken down

YouTube stars are complaining after hundreds of videos containing adverts for an essay-writing service were removed from their channels.

It follows a BBC Trending investigation which found more than 250 channels had YouTubers plugging EduBirdie.

Many of the adverts urge students to use EduBirdie to hire a "super smart nerd" to write their essays.

YouTube says promotion of essay-writing services is banned by its advertising policies.

The adverts appear in the middle of videos covering a range of interests including: pranks, video games, fashion and dating.

In most of them, the YouTube star breaks off from what they are doing, in order to promote EduBirdie.

The BBC investigation uncovered more than 1,400 videos with a total of more than 700 million views containing EduBirdie adverts.

In response to the discovery, universities minister Sam Gyimah said YouTube had a moral responsibility to act because the adverts were "enabling and normalising cheating potentially on an industrial scale."

Image caption Universities minister, Sam Gyimah, said the ads presented cheating as "a lifestyle choice"

YouTube emailed some channels warning that it would take down videos which contained EduBirdie adverts if they did not edit out the promotions by Friday.

Since then a wave of disgruntled YouTubers have turned to Twitter to complain at the removal of their videos.

One channel, To Catch A Cheater, said 49 of its videos - a year's worth of work - had disappeared.

AldosWorldTv said it had lost more than 30 videos, and questioned why he had been able to post so many videos containing the adverts.

TwinzTV, a US-based pranks channel posted on Twitter that "YouTube deleted 138 of our videos without any explanation".

Some YouTubers, like Patty Mayo, who makes bounty hunter videos, said they had been in the process of editing out the offending adverts when their videos were taken down.

In several of his ads Patty Mayo urged viewers to "hire the super smart nerds at Edubirdie.com to write your essays and your papers for you."

He told BBC Trending that he did not condone or endorse cheating.

YouTube has declined to comment on how many videos have come down, or if it also will allow channels to re-upload the videos without the adverts from EduBirdie, a company based in Ukraine.

In a statement given to the BBC last week it said: "YouTube creators may include paid endorsements as part of their content only if the product or service they are endorsing complies with our advertising policies.

"We do not allow ads for essay writing and so paid promotions of these services will be removed when we discover them. We will be working with creators going forward so they better understand that in video promotions must not promote dishonest activity."

Some YouTube stars including Adam Saleh and JMX had already taken down videos containing EduBirdie adverts before the purge on Friday.

Image copyright Adam Saleh Image caption Adam Saleh had already removed EduBirdie ads from his channel

Essay-writing services are not illegal. But any university student found to have submitted work done by someone else would face disciplinary action.

"If you've worked hard to get to university, you potentially throw it all away by cheating and getting found out. It is wrong, full stop," Mr Gyimah told the BBC.

EduBirdie is run by a company called Boosta which operates several online essay-writing companies. It says it cannot be held responsible for what social influencers say on their channels.

"We give influencers total freedom on how they prefer to present the EduBirdie platform to their audience in a way they feel would be most relevant to their viewers," its said in a statement.

"We do admit that many tend to copy and paste each others' shout-outs with a focus on 'get someone to do your homework for you', but this is their creative choice.

It added that a disclaimer on its website suggested work provided by EduBirdie was supplied only as a sample or a reference.

EduBirdie's own channel on YouTube has also been severely pruned back. Where once there were dozens of videos, there is now just one left, a guide to how to write an introduction to an essay.