SHOCK! Security called in after US One Direction fan walks in on half-naked Liam Payne
The band were at a New York gym when the girl managed to sneak past security to get a glimpse of her favourite boys in the buff.
'He was in the middle of getting dressed and had no idea what she was going to do, as their fans in the US are mad,' a source tells The Sun.
And Liam has revealed that American fans of Harry Styles, 18, are even more desperate to photograph him working out.
'We were in the gym after we checked into the hotel and people were trying to film Harry,' Liam, 18, tells the Daily Star.
'Loads of fans have been in the hotel lobby - and some of them even check in.
'I don't know how they can afford it.'
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