Two Married At First Sight UK stars say they were sexually assaulted on show

A BBC Panorama investigation

Another woman said she faced sexual misconduct from her husband while filming the Channel 4 social experiment, according to a BBC Panorama investigation.

The show, which is also a huge hit in the US and Australia, involves couples marrying after meeting for the first time on their wedding day and going on honeymoon together and living together.

The three unnamed women have raised major concerns about the safety and welfare of female cast members on the reality show.

The allegations will be explored in the documentary: The Dark Side of Married at First Sight, which will be shown on Monday at 8pm on BBC One.

The men accused of the sex attacks deny the allegations.

The Panorama investigation will claim that producers have left vulnerable participants at risk of harm.

Channel 4 said in a statement: "We have not seen the programme and will comment when we know more."

The channel and CPL, the independent production company that makes the series, say their welfare protocols are robust and comprehensive.

The experts on MAFS UK are Paul Carrick Brunson, Charlene Douglas and Mel Schilling, who died aged 53 in March following a battle with colon cancer that spread to her lungs and brain.

BBC Panorama presenter Noor Nanji claims to have spoken to the three women who have accused their onscreen husbands of sexual misconduct.

It is understood that none of the couples are still together. The BBC declined to comment on when and where the alleged sex attacks took place.

Last summer, a bride claimed to have been sexually assaulted during one of the show's dinner parties.

A spokesperson for the show said at the time: "We are aware that a report has been made to police about an alleged sexual assault during the filming of a dinner party.

"We take any issues on the show incredibly seriously. Producers follow strict welfare protocols as the wellbeing of the cast is always the first priority.

"Support would be offered to anyone who wished to report a matter to the authorities, and naturally we would cooperate with any enquiries or investigations."

A source told The Sun: "The show's been criticised for throwing strangers together and sending them on honeymoon for viewers' entertainment.

"Now it's alleged someone was assaulted after tying the knot. It is a disastrous look for bosses."

The show sees matchmakers and relationship experts join strangers together in the hopes of finding love. At the end of their eight weeks together, the couples are asked if they want to stay married.

If you've been the victim of sexual assault, you can access help and resources via www.rapecrisis.org.uk or calling the national telephone helpline on 0808 802 9999.