souths hooker issac luke has become embroiled in a social media storm .
the 27-year-old had posted a heartfelt appeal to find a young injured fan .
but he was taunted by bulldog fans on instagram over his posts .
he lashed out at them , calling them ` lil poofters ' on saturday .
the offensive comment prompted an immediate social media backlash .
the post was immediately deleted and luke has since apologised .
the rabbitohs star is now under investigation by the nrl integrity unit .
it comes after souths sealed a bitter win over the bulldogs on friday .