The pop star was performing her hit single 'Just Dance' on her 'Monster Ball' world tour in Washington on Tuesday night (07.09.10) when she noticed an altercation break out between two people in front of the stage and quickly halted the music.
She said: "Stop fighting. Do not fight at this show."
To cheers from the audience, Gaga then asked: "Is she ok? Are they both ok? I don't know who hit who.
"I'm sorry. I just don't want you to fight. This is all about love and happiness. Only fake monster fighting."
Gaga – real name Stefani Germanotta – didn't immediately restart the show, instead indulging in some banter with her fans.
Striking a pose and gyrating around the stage the 24-year-old singer asked: "Do you think I'm sexy? I think you're sexy.
"I wasn't very cool when I was in high school, I used to get made fun of all the time so sometimes I really abuse this part of this show."
The singer then revealed that she hates people to tell her the truth.
She said: "Does everyone know what I hate more than anything? I hate the truth, in fact I hate the truth so much I prefer a giant dose of bulls**t any day."