The family of estate agent Suzy Lamplugh, who disappeared 16 years ago, say they are angry and frustrated that the man suspected of killing her will not be charged.

Police re-investigating her disappearance told a news conference in London on Tuesday that convicted murderer John Cannan remained the prime murder suspect.

But the Crown Prosecution Service has advised Scotland Yard detectives there is insufficient evidence to bring charges against him.

We would all like to see the final piece of the jigsaw puzzle fall into place for the Lamplugh family

Deputy Assistant Commissioner Bill Griffiths

Miss Lamplugh vanished in July 1986 after meeting a client called Mr Kipper to show him round a property in Fulham, south west London.

Her body has never been found, although she was declared dead in 1994.

Cannan, 47, who was jailed for life in 1989 for the rape and murder of newly-wed Shirley Banks in Bristol, was questioned by detectives last year about Miss Lamplugh and a new file was later submitted to the Crown Prosecution Service (CPS).

He has denied any involvement.

Deputy Assistant Commissioner Bill Griffiths said Cannan, a used car salesman from Sutton Coldfield in the Midlands, had not been eliminated as a suspect and the investigation was not over.

"More and more questions about his involvement remain unanswered," he said.

High profile

He also appealed for anyone who could assist the inquiry as a witness to come forward.

"It's never too late to speak to us," he said.

"We would all like to see that final piece of the jigsaw put in place to allow the Lamplugh family to move on."

Suzy Lamplugh's body has never been found

The case has been one of Britain's most high-profile investigations. Officers have examined thousands of lines of inquiry and conducted DNA testing on 800 unidentified bodies.

Miss Lamplugh's mother set up the Suzy Lamplugh Trust in her memory to raise employers' awareness about the dangers faced by their staff.

In May 2000, the investigation into Miss Lamplugh's disappearance was reopened.

Mr Griffiths said that since then detectives had used cutting edge technology and revisited and re-examined every piece of forensic evidence to try to find the killer.

"I and the other officers involved believe we are closer now to a prosecution than ever before," he said.

Family frustration

Miss Lamplugh's father Paul, speaking at Tuesday's news conference said the news was a defining moment for the family.

"We are greatly distressed and considerably angered that after all this time it is still not possible to prosecute the person who both us and the police believe killed Suzy," he said.

The least the offender can do now is tell us where the body is

Paul Lamplugh

"Until the new investigating team was appointed we were frustrated that the investigation was static and we have indeed been most disturbed as to how many opportunities have been missed in the past."

He thanked the police teams who had worked on the case over the past two years and praised their "professionalism, dedication and determination".

He added: "Suzy was a lovely girl and we and her brother and sisters and her many friends still miss her enormously.

"It's greatly distressing that Suzy's body has not been found nor do we know how she was killed.

"The least the offender can do now is tell us where the body is."