Bulk data storage allows for the "potential of abuse", President Obama has said, as he announced plans to curb the National Security Agency's authority.
"While few doubt the legitimacy of spying on hostile states, individuals acting on their own is a new threat," Mr Obama said.
"These signals intelligence efforts have prevented multiple attacks and saved innocent lives, not just in the United States but around the globe. But the risk of government overreach has also become more pronounced".
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ITV Border Political Editor Peter MacMahon says it's far too early to call this referendum.
A World War Two veteran has told ITV News he has fulfilled a boyhood dream by voting for an independent Scotland.
Keep on top of the referendum results as they are announced from 32 counting stations across Scotland.