A string of organisations critical of the new Relationships and Sex Education curriculum have had their Twitter accounts suspended.
The accounts of Parent Power, 40 Days UK, Voice for Justice UK and RSE Authentic have all been suspended by Twitter in the last week.
RSE Authentic and 40 Days UK are both linked to the Values Foundation, an organisation that seeks to represent faith and traditional family values in the educational sector, while Parent Power has ties to Voice for Justice UK, a charity that advocates for Christian freedoms and values in the UK.
All of the organisations take a traditional view of marriage and sexuality, and have questioned the Government's new Relationships and Sex Education curriculum (RSE), which became mandatory in schools at the start of September.
Nigel Steele, director of the Values Foundation, said it was "particularly strange" that some of the accounts were suspended as they are "used infrequently".
He said the suspensions had happened "without any proper explanation" from Twitter.
The accounts were suspended within days of a report in the Byline Times which cast the groups' advocacy work on RSE in a negative light.
The suspended accounts display a message stating that "Twitter suspends accounts which violate the Twitter Rules".
The Twitter Rules include a section on "hateful conduct", which prohibits "content that intends to dehumanize, degrade or reinforce negative or harmful stereotypes about a protected category".
In June, Twitter permanently suspended the account of Father Ted writer Graham Linehan over a "'hateful conduct rules breach" after he reportedly tweeted "men aren't women tho" in response to the Women's Institute's post wishing a happy Pride to transgender members.
Last month, Twitter apologised after temporarily suspending the account of conservative satire site the Babylon Bee. A spokesperson for Twitter claimed that the site "was mistakenly caught in a spam filter".
Last year, the Twitter account of pro-life movie Unplanned was suspended and later reinstated after public outcry.