“The National Security Agency lost its authority to use several electronic spying tools that President Barack Obama deems critical to combating terrorism, when Rand Paul, a Republican senator, blocked efforts to prevent the measures from expiring at midnight on Sunday,” The Financial Times reports.  

“The Senate held a rare Sunday session to attempt to find a compromise but Mr Paul, who is running for the Republican presidential nomination, blocked efforts to prevent the tools from expiring at midnight. Instead, the Senate voted 77-17 to start debating a compromise bill called the USA Freedom Act that the House of Representatives passed this month.”  

“Mr Paul also used parliamentary procedures to push back debate on the bill, meaning the NSA will almost certainly lose the ability to use certain tools for a couple of days. However, he faces an almost impossible battle to impede final passage, given the large number of senators — more than the 60 needed to prevent a filibuster — who appear willing to support the House bill.”  

“Two other programmes also lapsed at midnight. One involves the ability to track “lone wolf” terrorism suspects, while the other allows the NSA to monitor calls from people who frequently discard mobile phones.”