Up to ten mobile phones and computer gadgets potentially linked to Rebekah Brooks have never been found by police, the hacking trial heard.
An iPhone, an iPad and "unknown device" listed on Brooks' home router were never recovered in searches on the former News International chief executive's office and addresses in London and Oxfordshire, Detective Constable Philip Stead told the court.
News International also provided details of three BlackBerry phones, an HTC phone, two Apple iPhones and an Apple iPad thought to be linked to Brooks.
In all, the court heard there were up to 10 devices in use up until September 2011 unaccounted for by police.
However, one phone may be a duplication, another may belong to someone else and an Apple iPad may have been lost.
It has recently come to light that one of the phones linked to the Oxfordshire router has since been claimed by Sir Charles Dunstone, the Carphone Warehouse boss, Det Con Stead said.
The judge Mr Justice Saunders quipped to the jury: "He probably has a lot of phones!"
The trial has heard previously how Brooks left with just her handbag and a disabled BlackBerry phone after she resigned from her job in July 2011.
Her office was sealed off by NI staff and computer equipment bagged up by police for examination.
Police later seized computer equipment in a search of Brooks' London home while she was in custody at Lewisham Police Station and were handed two bags containing two laptops stashed overnight in the underground car park of the Chelsea Harbour flat.
Jonathan Laidlaw, QC, defending Brooks, suggested explanations for the missing devices – that they may have been broken or lost and replaced.
Referring to the BlackBerry phones on the list of missing devices, he asked Stead: "Would you be able to say whether or not 4, 5 or 6 may simply be early BlackBerrys issued to Mrs Brooks?"
He replied: "I do not think you can tell."
Laidlaw pressed: "We will never know will we?", to which the witness replied: "No, not in relation to these devices."
Laidlaw went on to cite an email exchange between Brooks and her husband Charlie on 1April 2011.
Responding to the message she had "Lost iPad 2", Mr Brooks replies: "Back of car from last night?
Later, the court heard that the News International system of tracking the allocation of technology to staff had been in need of improvement and it was not until August 2011 that a new system was brought in.
On the evidence gleaned from the router at Brooks' Oxfordshire home, Laidlaw said: "All this tells you is there has been a connection. It does not necessarily tell you there has been activity."
Brooks, 44, of Churchill, Oxfordshire, denies conspiring to hack phones, conspiring to commit misconduct in a public office and conspiring to pervert the course of justice.
All seven defendants in the case deny the charges against them.
The trial was adjourned until 10am on Monday.