EastEnders fans have criticised the soap after last night's plot twist, which implied Keanu could be the father of half sister Bernadette's unborn baby.

EastEnders writers have been accused of going a step too far after an apparent plot twist involving incest.

Last night’s episode saw the shock revelation that the father of character Bernadette Taylor’s unborn baby could be her half brother Keanu.

Character Karen Taylor has been attempting to discover who the father of her 15-year-old daughter’s baby is since Monday’s episode, but fans couldn’t quite believe the storyline development.

Keanu is played by Danny Walters

The episode showed Karen learn the news after overhearing her son promise her daughter – his half sister – he would support the baby financially and keep his identity as the father a secret.

The Sun reported that the soap received its lowest ever ratings as sickened viewers shunned the show.

The episode – which aired on BBC Two due to Wimbledon – fell to just 3.41m viewers amid a deepening crisis over axed producer Sean O’Connor’s brief tenure in charge.

Fans expressed their shock on social media.

@lesley777 tweeted: Surely EastEnders aren’t going down the incest route? It will truly be a new low. 

@fashionhoelewis wrote: eastenders pulling an incest storyline i’m done with that show

@TheOwenChild tweeted: Keanu is Bernadette’s baby Dad as well as being her brother! Incest storyline eughh

@AndrewGrabham wrote: Really don’t wanna see an incest storyline on EastEnders if I’m honest

But others believed the plot twist was merely a red herring.

@iananthonyluke tweeted: This can’t be how it seems! He just has to know who the father is! If this is some twisted incest storyline I’ll scream! #Eastenders

EastEnders continues next week on BBC1.