[MarkWaldorf]

just further evidence of why i hate what she's become.

Lady GaGa caused chaos at her O2 concert last night, according to a report.

The 'Bad Romance' singer allegedly went "bananas" and screamed at her costume director, before illegally chain-smoking and spitting out food.

A source told the Sunday Mirror: "First she started screaming at her costume director when something didn't look right. Then she grabbed a cigarette and proceeded to chain-smoke for the next half hour despite being told it wasn't allowed. She started screaming at them and they looked petrified."

"She went bananas when she saw cartons and cans in the room. She demanded glasses saying she, 'Wouldn't drink out of that sh*t'. She spat out the fried chicken laid on for her after one bite and said it tasted, 'Wrong'. Then she made three of her entourage go out and find fried chicken that would be, 'More American'."

The source added: "They've even had a few of her dancers back to their hotel room and she makes no bones about hiding that fact. Matt [Williams, GaGa's boyfriend], who she calls DaDa, just puts up with it because he's so in love, but he's the only one allowed to speak back to her."

Meanwhile, at the gig, Cheryl Cole - who has been the subject of much media speculation this week - had to be escorted out of the sound decks and to a quieter area after the star started "getting too much attention".

"Cheryl was going to be watching the gig from the sound decks but it became evident she was getting too much attention, so they whisked her into a quieter box with friends," the source said.

- Digital Spy