South Sydney's Kiwi hooker Issac Luke is under investigation by the NRL integrity unit after posting a homophobic slur on Instagram.

In the continuing fallout from the Rabbitohs' controversial 18-17 Easter Friday win over Canterbury, Luke posted the offensive comment on the social media site in response to attacks from Bulldogs fans.

"get off my page you lil poofters" Luke wrote.

"This is about a kid your fans knocked out. Well now two kids Yous dropped. We train at Redfern come down and see if you fellas are still carrying on #rulesarerules even though it was a hard penalty to take. I bet yous would've done the same had we done it to one of your players. Or we would've have even had u gooses commenting had it happened earlier on in the game. Now get off my page."


Luke later deleted the post.

Luke said was attempting to get in contact with a young Rabbitohs fan who was allegedly attacked in the ANZ Stadium crowd during the round five fixture.

His first post read: "Just reaching out to the SSTID FANS on the whereabouts of the young SOUTHS fan who ended up in hospital last night. We have something for him."

Last year Luke fell foul of the NRL when he used the social media platform to say he intended paying tribute to Rabbitohs teammate Kirisome Auva'a in the Four Nations final, after Auva'a was suspended from the NRL after pleading guilty to domestic assault charges.

Luke's post on Saturday comes after Waratahs forward Jacques Potgieter was fined $10,000 by the ARU for making an on-field homophobic slur.