ONE of Suffolk police's leading detectives is set to retire after 39 years with the force.Detective superintendent Roy Lambert, who is heading the investigation into the death of Ipswich prostitute Anneli Alderton, will leave his role in May.

ONE of Suffolk police's leading detectives is set to retire after 39 years with the force.

Detective superintendent Roy Lambert, who is heading the investigation into the death of Ipswich prostitute Anneli Alderton, will leave his role in May.

But the 55-year-old will remain with Suffolk Constabulary in a civilian position until Operation Sumac - the probe into the killings of five Ipswich prostitutes - is complete.

Mr Lambert, who joined Suffolk Constabulary as a cadet from school in 1968, is the force's most experienced senior investigating officer.

He has cracked a series of high-profile inquiries during his long career, including armed robbery, drug peddling and a bombing campaign. He has led probes into the murders of teenager Vicky Hall, who was killed in 1999, and pensioner Joan Albert, who was found dead at her Capel St Mary home in 2001.

Last year, he secured the conviction of Kevin Nunn, who was found guilty of murdering his ex-girlfriend Dawn Walker, in February 2005.

Mr Lambert first walked the beat as a uniformed bobby in Felixstowe and later in Brandon at the age of 19, in 1970.

In March 1981, then aged 30 and working as a detective sergeant, he was confronted by a criminal armed with a sawn-off shotgun.

The gunman shot at Mr Lambert and another detective, both of whom were unarmed and only around 15 feet away.

Mr Lambert was later presented with the Queen's Commendation for Brave Conduct and was praised for his “very gallant action in the line of duty”