During her performace at the Citibank Hall in Rio de Janeiro recently, an over-excited fan apparently bit a security guard after he tried to remove her from stage during the show, reported Ace Showbiz.
"Apparently some girl bit one of my security guards after she jumped on stage and I never even noticed," Lovato, 21 tweeted.
The singer will have some more shows in Brazil before bringing the concert to other countries including Argentina, Chile and Panama.
The European leg of her "Neon Lights" Tour will kick off on June 1 in England.