White House spokesman Jay Carney says the FBI is conducting further tests to confirm the initial readings that the letters contained the poison ricin.

白宫发言人杰伊·卡尼表示，联邦调查局正在进行进一步的检测，初步检测结果表明信件中含有蓖麻毒素。

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So if it gets strong indications that organisms might be present, it will be able to subject samples to a wide range of tests to confirm initial readings.

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