Westboro Baptist Church is to picket the funeral of Sylvester Stallone's son, Sage, who was found dead last week.

Hours after news of the 36-year-old's death emerged, Westboro member Margie Phelps tweeted: "Thrice-married rebel taught his son to mock God. ‪#picketfuneral‬ MT@digitalspy: Sylvester Stallone's son Sage Stallone found dead, aged 36."

Westboro Baptist Church has become famous for its vulgar pickets at the funerals of fallen soldiers and others.

Margie Phelps is the daughter of Fred Phelps, the patriarch of the fundamentalist church, which is based in Topeka, Kansas, and made up mainly of Phelps family members.

She continued on Twitter: "Adulterous dad brought wrath of God on son. ‪#BloodOnDadsHands‬‪#picketfuneral‬ ‪#woe‬ MT @GlobalGrind: Sylvester Stallone son, Sage, dead at 36."

She had more harsh words for Sylvester Stallone: "Chance to redeem yourself with God. Tell @TheSlyStallone to mourn for his sins, not pimp out son's dead body to more proud sin!"

Sage was found dead in his home in Studio City, Los Angeles, by his housekeeper on Friday.

An autopsy has been carried out but the cause of death remains unknown. A toxicology report is pending.

According to media reports, Sage had been due to marry his long-time girlfriend in Las Vegas on Sunday.

Sage was Sylvester Stallone's son to ex-wife Sasha Czack.