Leslie Grantham is "fighting for his life" as he battles a mystery illness.
The "EastEnders" legend - who was known for his role as Albert Square hard man "Dirty" Den Watts from 1985 to 1989, and then again from 2003 to 2005 - is said to be being closely monitored by doctors after returning to the UK from Bulgaria, where he has spent the past few years, and falling gravely ill.
A close friend told The Sun newspaper: "Leslie is being looked after. Those who are close to him are hugely worried and are praying for his well-being."
And a spokeswoman for Leslie confirmed: "It's true that Leslie is very poorly."
As of the time of writing, the illness plaguing the soap star has not yet been made public, and further details on his condition are not yet known.
The 71-year-old actor hand moved out the UK following his split from his wife Jane in 2013, after 31 years of marriage, and chose Bulgaria after having spent time in the country whilst filming soap "The English Neighbour" in 2010.
Leslie famously starred in BBC soap "EastEnders" as villain Den Watts, who was supposedly shot dead next to a canal in 1989 during an attempted bid to leave the country, with on-screen daughter Sharon Watts even identifying his body.
But that didn't stop soap bosses from reviving his character and bringing him back from the dead in 2003, when he was reunited with Sharon in what marked one of the soap's most shocking storylines.
Leslie's run as the soap baddie was made even more believable by his own criminal past, as before joining the soap, he had spent a decade behind bars from 1967 for the murder of a German taxi driver.
During his time in prison, Leslie learned how to act and performed in plays for the benefit of inmates.