#Social media users have been swapping their profile picture for comic book heroes in an attempt to raise awareness about childhood cancer.
As part of Childhood Cancer Awareness month, US Facebook users in different cities have been representing themselves as their favourite cartoon superhero this September.
The campaign, whose origin is unclear, urges others to take part by assigning a character to those who like the new profile.
Statuses must read: "I intend to fill Facebook with comic book heroes for Childhood Cancer Awareness! Give me a like and I'll assign you a character."
Different Facebook groups representing cities have started their own pages dedicated to the cause. A Facebook group for Childhood Cancer Superheroes of Alabama shows a Giant Hulk fist smashing into the malignant disease.
In the US, one in 285 children will be diagnosed with cancer before age 20, according to the American Cancer Society.
The most common cancers in children are acute lymphocytic leukemia and brain cancer, while the most common in teenagers are Hodgkin lymphoma and thryroid carcinoma.
The online cause gained more attention in the US recently when 700 campaigners sitting in a park near the White House were removed by security officials as part of protocol to allow President Barack Obama to leave.
According to CNN, the Secret Service moved the group, which included children, out of Lafayette Square despite their having obtained a permit to stay there.
The security body later issued an apology for not communicating more clearly with parents and children.
This is not the first time cartoon characters have been used to raise awareness. In 2010, Facebook users did the same to start a discussion about child abuse.