A neighbour said she heard a girl's screams but didn't realise what was going on.
Ronke Phillips reports.
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Detective Constable Kevin Rowley appeared at Westminster Magistrates' Court on Monday charged with assaulting the teenager by beating him.
The Royal Observatory in Greenwich streamed the event online using state of the art telescopes.
Speaking to ITV News Simon Wilkinson said the company had no phone number for the former staff members and they didn't respond to emails.