THREE Dorset Police officers have been served with gross misconduct notices for their handling of vulnerable Phillip Nicholson in the months before his murder.

The officers, who have not been identified, face an investigation by the Independent Police Complaints Commission (IPCC).

The force referred itself to the IPCC two days after Mr Nicholson was lured to his ex-partner's flat in Sea Road, Boscombe, before being knifed to death by her new boyfriend.

Isabella Gossling, 20, was this month convicted at Winchester Crown Court of murdering the victim on May 26 this year, and sentenced to life in prison.

She will serve at least 19 before she can be considered for release.

Richard Moors, 26, had admitted murder at an earlier hearing.

He was also sentenced to life behind bars, with a minimum term of 22 years to serve before he can be released.

Police had been called in as a result of concerns about the relationship between Mr Nicholson and Gossling around 18 months before the 22-year-old was killed in a 17-minute attack recorded in its entirety on Gossling's mobile phone.

Mr Nicholson had been assessed as being at very high risk of sexual, mental, financial and emotional abuse by an independent domestic violence advisor.

He had an IQ of 62 and lived in assisted accommodation in Parkstone.

A spokesperson from the IPCC said the organisation is resuming its investigation into Dorset Police following Gossling's conviction.

"The IPCC investigation is looking at how Dorset Police officers investigated threats against Mr Nicholson in the 18 months before his death, including one made 11 days before his fatal stabbing," the spokesperson said.

"It will also look at whether police acted appropriately in their dealings with Mr Nicholson.

"The investigation began following a referral from Dorset Police on May 28 2015 after Mr Nicholson was killed, and was suspended while criminal proceedings were underway. It has now resumed following the conviction of Ms Gossling on December 9 2015.

"At this stage, three Dorset Police officers have been served with gross misconduct notices informing them that their conduct is under investigation."

Misconduct notices do not imply guilt but are to inform the officer that their behaviour and conduct are under investigation and the level of severity.