It's an electronic game of cat-and-mouse that could have deadly consequences if a plot is missed or a terrorist operative manages to drop out of sight.
Two US intelligence officials say members of virtually every terrorist group, including core al-Qaeda, are attempting to change how they communicate, based on what they are reading in the media, to hide from US surveillance -- the first time intelligence officials have described which groups are reacting to the leaks.
The officials wouldn't go into details on how they know this, whether it's terrorists switching email accounts or cellphone providers or adopting new encryption techniques, but a lawmaker briefed on the matter said al-Qaeda's Yemeni offshoot, al-Qaeda in the Arabian Peninsula, has been among the first to alter how it reaches out to its operatives.
The lawmaker spoke anonymously because he would not discuss the confidential briefing by name.
Shortly after Edward Snowden leaked documents about the secret NSA surveillance programmes, chat rooms and websites used by like-minded extremists and would-be recruits advised users how to avoid NSA detection, from telling them not to use their real phone numbers to recommending specific online software programmes to keep spies from tracking their computers' physical locations.
Senator Angus King said yesterday that Snowden "has basically alerted people who are enemies of this country ... (like) al-Qaeda, about what techniques we have been using to monitor their activities and foil plots, and compromised those efforts, and it's very conceivable that people will die as a result."
At the same time, NSA and other counterterrorist analysts have been focusing their attention on the terrorists, watching their electronic communications and logging all changes, including following which Internet sites the terrorist suspects visit, trying to determine what system they might choose to avoid future detection, according to a former senior intelligence official speaking anonymously as a condition of discussing the intelligence operations.
You’ve reached your limit of {{free_limit}} free articles this month.
Subscribe now for unlimited access.
Already subscribed? Log in
Subscribe to read the full story →
Smart Quarterly
₹900
3 Months
₹300/Month
Smart Essential
₹2,700
1 Year
₹225/Month
Super Saver
₹3,900
2 Years
₹162/Month
Renews automatically, cancel anytime
Here’s what’s included in our digital subscription plans
Exclusive premium stories online
Over 30 premium stories daily, handpicked by our editors


Complimentary Access to The New York Times
News, Games, Cooking, Audio, Wirecutter & The Athletic
Business Standard Epaper
Digital replica of our daily newspaper — with options to read, save, and share


Curated Newsletters
Insights on markets, finance, politics, tech, and more delivered to your inbox
Market Analysis & Investment Insights
In-depth market analysis & insights with access to The Smart Investor


Archives
Repository of articles and publications dating back to 1997
Ad-free Reading
Uninterrupted reading experience with no advertisements


Seamless Access Across All Devices
Access Business Standard across devices — mobile, tablet, or PC, via web or app
