One Direction security stepped up in US after Niall Horan mobbed in Times Square
One Direction are causing such a frenzy in America that the police have twice been called to where they're staying in New York - prompting their management to heighten security around the boys.
Niall Horan, 18, was mobbed as he attempted to take photos in Times Square and had to return with his minder to the band's hotel, which was surrounded by admirers.
'Fans were crying and shaking when they caught a glimpse of the band,' a witness tells Metro.
'It was very surreal.
'Others were banging on the glass of the windows and hotel managers were worried they would smash the glass.'
Fears for The X Factor finalists' safety comes after their debut album Up All Night reached No 1 in the US iTunes chart and their mini concert at the city's Rockefeller Plaza gathered a record-breaking crowd of 15,000.
The boys also treated Z100 listeners to an acoustic web performance that drew in 40,000 listeners - 6 times more than Justin Bieber.
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