The Guardian understands the dramatic increase in security was carried out on the basis of an alert that came from a long-term intelligence source who has proved reliable in the past.

据卫报了解，这种安保力量的戏剧性增长是在一项长期情报源发出警告后实行的，在过去，这一情报源已证实了它的可靠性。

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Intelligence experts are concerned the latest alert, while possibly averting a disaster, could compromise possible intelligence networks.

情报专家对最新的警告表示关注，虽然这可能避免了一场灾难，但是也可能使得导致发出这项警告的情报来源曝光。

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The key, security experts say, is to stay alert and vigilant, preventing an attack before it happens and that, in turn, demands good intelligence.

安全专家表示，关键是保持警惕，在袭击发生之前将它们阻止。反过来，这需要充分的情报。

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Speaking to local media, Pakistani Interior Minister Rehman Malik said intelligence agencies had expected attacks on security sites in the country and that authorities will remain on high-alert.

VOA: standard.2009.10.15

The Israeli prime minister was not interested in relying on intelligence assessments to alert the world to a bomb-making programme.

BBC: Netanyahu, Abbas display divergent priorities at UN

But a U.S. intelligence source tells news alert!

CENTERFORSECURITYPOLICY: Security Meltdown at State Department Start at the Top

Many governments were already on a heightened state of alert due to vague but persistent intelligence suggesting an attack may be imminent in Europe or elsewhere.

WSJ: Nations Brace for Retaliation After Osama Bin Laden's Death