A 21-year-old man has been charged with the murder of schoolgirl Arsema Dawit.

The 15-year-old was stabbed up to ten times in a frenzied attack in the lift of the block of flats where she lived with her family in south London.

Thomas Nugusse, 21, a student, of Ilford, Essex will appear on the charge at Greenwich Magistrates Court on Thursday, Scotland Yard said.

Meanwhile, the police watchdog is to investigate the handling of complaints from Arsema's family.

Weeks ago Arsema's family told police that she had been assaulted by an obsessive man described as being in his 30s. But they said officers told them there was nothing they could do about the man who met her at an Eritrean church where she was a member of the choir.

In a statement, the Independent Police Complaints Commission (IPCC) said it had asked the Metropolitan Police to refer the investigation to it.

"The family complained to the Metropolitan Police that Arsema, 15, was assaulted on 30 April, five weeks before her murder in Waterloo," the statement read.

"The IPCC awaits the referral, whereupon the Commission will assess how the investigation should be carried out."

An officer spoke to the girl at her school on May 12 but she claimed to have "no knowledge" of the incident.

Police contacted Arsema's mother a week later and the investigation was still ongoing when she was murdered on Monday.

One source close to the inquiry said officers were not aware of a wider campaign of harassment against the schoolgirl.

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