Experts analysing a computer hard disk seized from the home of Khafeel Ahmed, a suspect in the foiled terror plot in Britain, are focussing on innocuous key words, numbers or bits of information that may contain encrypted data, police sources said on Wednesday.

A phrase like 'meeting at a tea shop' could actually mean something deeper and could signal something that was specific
to the execution of a task by terrorists, an official said.

Words that appear to be otherwise innocuous and ones that would raise little doubt when used in a daily context are
often used by terrorists while communicating with each other to steer clear of monitoring by authorities, the sources said.

During the Mumbai train blasts last year, the words 'davat hui' (the invitation has been sent) were used to send across
the message to those involved in the conspiracy that bombs planted in the trains had exploded, they said.

Police had sent the hard disk to the Thiruvananthapuram-based Resource Centre for Cyber Forensics at the Centre for Development of Advanced Computing Technology to ensure that 'no chances' were taken and that they were able
to extract all the information on the disk.

Besides the play of words, the decoding of computer data depends on the programmes run, software used and various
configurations within it, said a cyber crime official. The time to decode such information would depend on these factors,
he said.

Simple sounding words might hold potential clues and it is the cracking of these words that makes all the difference to a
case, the official said.