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(S//SI) SIGINT Contribution to Operation CREVICE
FROM:
UK Liaison Team
Run Date: 04/19/2004
FROM:
UK Liaison Team
(S//SI//REL) You probably saw DIRNSA's message to the work force , thanking you for your
work on Operation CREVICE. If that sparked your interest, read on to find out a bit more about
the operation...
(S//SI) Op CREVICE
(TS//SI) Since March 2003, the UK's Security Service and police had been investigating an AQ
(al-Qa'ida) support network based in the UK with links to a senior AQ operational planner in
Pakistan.
(TS//SI) In February, the UK authorities stepped up their efforts in response to key intelligence
revealing that a UK-based member of the network was attempting to mount an attack in the UK
using a large improvised explosive device. In addition, the Pakistan-based contact was
attempting to obtain nuclear material for use in the device, which was apparently to be deployed
in the near future.
(U) SIGINT Contribution
(TS//SI) It was actually an NSA SIGINT report that sparked the heightened level of interest in
the Operation, as the report involved a Pakistan-based and UK-based individual discussing,
amongst other things, the composition of a probable explosive.
(TS//SI) During February and March, GCHQ (Government Communications Headquarters)
provided reporting which helped assist Pakistani authorities in locating and detaining the
Pakistan-based individual. Call records analysis and reporting expanded Security Service's
network knowledge and helped to identify new telephone numbers of key targets in the UK. C2C
(computer-to-computer) analysis provided new leads on a Canada-based individual within the
network, and other reporting helped to validate the activities of one of the key overseas
members of the network.
(TS//SI) Overall, well over 100 SIGINT reports were issued on Operation CREVICE. Although the
majority of End Product was GCHQ originated, the NSA reporting contributed significant pieces
to the jigsaw.
(TS//SI) Now that arrests have been made, GCHQ is monitoring for any further significant
activity, and End Product has been issued on various individuals spreading news of the arrests.
In addition, GCHQ is likely to receive more targeting information from Security Service as the
investigation continues.
"(U//FOUO) SIDtoday articles may not be republished or reposted outside NSANet
without the consent of S0121 (DL sid_comms)."
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DERIVED FROM: NSA/CSSM 1-52, DATED 08 JAN 2007 DECLASSIFY ON: 20320108
