Singer Pete Doherty will not face charges over the death of a man at a party in East London four years, the CPS said today.

Cambridge graduate and actor Mark Blanco, 30, died after plunging from the first balcony of a flat in Whitechapel in December 2006 after a confrontation with the Babyshambles singer.

But today his mother Sheila Blanco, who has campaigned to get the case brought to trial, was told by prosecutors that the singer and his minder Johnny Jeannevol and writer Paul Roundhill, who were also at the party, will not be charged.

Ms Blanco has vowed she “will not go away” and said earlier this week she would consider bringing a private prosecution if the CPS decide not to take the case further.

She said today she was “disappointed but not surprised” by the decision, adding: “It is a police cover-up. I really did not expect anything better.”

The CPS said today there was insufficient evidence to charge anyone over the death.

Jenny Hopkins, from the CPS, said: “None of the evidence is capable of establishing to the required standard that Mr Blanco was thrown or pushed from the balcony or that any other individual was present at the time he fell.”

Ms Blanco has spent thousands on collecting her own evidence and on legal fees over the past four years.

She funded a pathologist’s report which concluded that by the nature of the injuries, Mr Blanco could not have deliberately jumped.

An initial Metropolitan police investigation found that Mr Blanco did jumped deliberately but a coroner later recorded an open verdict into the death.

Ms Blanco has consistently said she felt let down by the police investigation, accusing the force of not investigating the case properly.