The hip-hop star was performing his hit song Wild Thing at the #ILoveThe90s concert in Sioux Falls when he had to be helped offstage after he halted the song as his legs began to buckle, according to multiple reports.

The 50-year-old signalled security staff to help him and was attended to by medical experts backstage before returning to the stage to complete his set.

This isn't the first time Tone Loc, real name Anthony Terrell Smith, has passed out while performing - in 2013 he collapsed at a show in Des Moines, Iowa. The concert was immediately cancelled and Loc received medical attention. TMZ reports Loc also collapsed onstage in 2012, 2011 and 2009.

It is still not clear what caused his latest incident.