Four serving Sussex Police officers are being investigated over their handling of a reported sexual assault carried out by Jimmy Savile.

The Independent Police Complaints Commission (IPCC) launched formal procedures against the force in November last year.

The probe is concerned with their handling of a reported assault carried out by the now dead TV personality in 1970 – which was made in 2008.

Two of the officers, a detective sergeant and detective constable, who visited the Worthing woman over the alleged sexual offence, have been served with gross misconduct notices.

The two other officers, a detective chief inspector and detective inspector, who had supervisory roles, have received misconduct notices.

IPCC deputy chair, Sarah Green, who is overseeing Savile investigations, said: "The investigation is examining interactions between Sussex Police officers and the victim and whether all lines of enquiry were properly pursued.”

Last year the director of Public Prosecutions published a highly critical report into the force’s handling of the alleged offence.

A Sussex Police spokeswoman said they would “fully co-operate” with the independent investigation.

She added: “In the course of the investigation, liaison was established with Surrey Police through the then Impact Intelligence National Index (INI) and it was established that a similar investigation was under way in that force relating to allegations against Savile.

“The woman who made the Worthing allegation did not wish to give evidence in court, and in the absence of other corroborating evidence, a decision was therefore taken by supervising detectives not to take further action in the that case.

“Nonetheless details of the Sussex report were forwarded to Surrey and were amongst the material submitted by Surrey Police to the Crown Prosecution Service (CPS), who subsequently decided that there should be no criminal proceedings against Savile.”

She said the force had accepted more could have been done to reassure the person reporting the allegation and that a more proactive approach could have been taken to explore intelligence about other alleged offending by Savile.

She added: “We also recognised that we could have done better and are committed to honest reflection and learning lessons for the future. Our priority in such cases continues to be professional and compassionate, with a focus on achieving the best outcome for victims whilst respecting their wishes.”