The Warwick Rowers' official website was knocked offline in an alleged DDoS attack after its popular nude calendar was rejected in Russia. REUTERS/Eddie Keogh

The website used to sell merchandise for the University of Warwick's rowing club, including a nude calendar, produced every year to raise money for charity, was hit with a DDoS attack this week after the team magazine was banned for sale in Russia. Every year, the university's rowing club poses nude for the Warwick Rowers calendar to raise funds for Sport Allies, an LGBT charity that promotes diversity and tackles homophobia and gender bias in the sport.

The calendar features students from the University of Warwick's rowing team strategically posing in various stages of undress in different sites.

However, the 2018 edition of the popular, award-winning calendar was reportedly been turned back at the Russian border.

Angus Malcolm, the calendar's producer and photographer, told the Independent that the calendars would have been stopped by UK customs if there was a physical issue with them or if they did not meet trading standards.

Malcolm believes the rejections were likely to do with Russia's controversial "gay propaganda" law that forbids the promotion of "non-traditional sexual relations among minors."

"We can't think of any other plausible reason," Malcolm told The Times. "We've had six instances of calendars being rejected by Russian customs. All had been ordered by people with male names. We have several more orders [to Russia] in the pipeline and don't yet know whether they will come back."

Six of the 23 calendars shipped to Russia have been returned, Malcolm said.

A few days after the calendars were rejected, the Warwick Rowers was allegedly hit with a DDoS attack, knocking it offline. They said the attack sent "7,268 visits per second" to their website and reportedly traced back to an IP address in Russia.

"Either that was someone who really didn't want any more of those calendars being sold, or it was one person who was very keen indeed to purchase a calendar for each and every one of his comrades," security expert Graham Cluley wrote in a blog post.

It is unclear if the attack was state-sponsored or carried out by a lone threat actor. The website was live and functioning normally at the time of publication.

"My heart goes out to the rowers' Russian fans, who are increasingly subjected to acts of hatred and discrimination that shouldn't be tolerated in any society anywhere across the globe," Malcolm told The Independent.

"The fact Russian customs rejected our calendar is nothing compared to the suffering some LGBT+ people face every day, but it acts as a signifier of the wider problem. If they can't cope with a few naked bums, then frankly that's quite sad."

He also took aim at Russian President Vladimir Putin saying he promotes "precisely the kind of toxic masculinity that Sport Allies and the Warwick Rowers want to challenge".

"With the rise of Putin's brand of populism around the world, we have never needed straight allies like the Warwick Rowers more than we do now," he said.