Two British-born Islamic extremists used a laptop to hold "silent conversations" about terrorist plans that included Royal Wootton Bassett as a potential target, a court heard today.
Richard Dart and Imran Mahmood tried to avoid surveillance by typing into a Word document on a laptop rather than speaking aloud, prosecutors claim.
Dart, 30, who is originally from Dorset and is the son of teachers, was trying to get advice from Mahmood about getting terrorist training in Pakistan.
He, Mahmood and co-defendant Jahangir Alom all admitted engaging in conduct in preparation of acts of terrorism last month.
Today the sentencing process, which could take until tomorrow, began at the Old Bailey.
Prosecutor Jonathan Laidlaw QC told the court: "The method employed as the police, with the help of computer experts, would subsequently discover, involved Dart and Mahmood sitting together at a computer and opening a Word document on the computer to conduct what in effect was a silent conversation.
"Having had that discussion by typing into the document, the document was then deleted by one or other of the defendants, without having been saved and as far as the defendants were concerned the document would therefore be destroyed forever.
"They plainly were under the misapprehension that the text once deleted could never be recovered."
The tactic suggested that they were aware that they might be under surveillance, the court heard.
Mr Laidlaw added: "It is obvious, suggest the prosecution, from the covert method of communication employed that they were surveillance conscious and had received anti-surveillance instruction or training.
"They knew that their activities were likely to be of interest to the authorities and that ordinary conversation within their homes may be recorded by listening devices."
In the conversations, Dart asked Mahmood about getting contacts with the Pakistan Taliban, Tehrik-i-Taliban Pakistan, which was banned in the UK in 2011.
The pair discussed how to make explosives, and Mahmood made reference to military tribute town Wootton Bassett as a potential target.
He went on: "They're all combatant so if it comes down to it, it's that or even just to deal with a few MI5, MI6 heads".
He also said: "The real war is here not over there".
Dart of Broadway, Ealing, west London; Mahmood, 22, from Dabbs Hill Lane, Northolt, west London, and Alom, 26, of Abbey Road, Stratford, east London, were all Islamic extremists "committed" to terrorism, Mr Laidlaw said.
Alom had his own contact with a fourth man, Mohammed Tariq Nasar, a Briton living in Pakistan, to try to get terrorist training, it is claimed. Mr Nasar has not been charged with any offence.
Prosecutors say that all three defendants travelled to Pakistan for terrorist training, although Dart and Alom were unsuccessful in that aim.
The trial continues