The police and intelligence services launched an enormous investigation to prevent the attacks, employing 200 people to provide round-the-clock surveillance.

警局和调查局发起了大规模的调查以防攻击，并雇佣200人员进行24小时监督。

youdao

The investigation failed to provide enough evidence to form the basis of a case, however.

然而这项调查没有提供足够的证据，以构成这一案例的根据。

youdao

Wang of the prosecutor's office said the investigation is still ongoing, but declined to provide further details.

台北地检署发言人王文德说，相关部门的调查依然在进行，他拒绝提供进一步的细节。

youdao

Officials refused to provide details about Thursday's searches and detentions, citing the ongoing investigation.

VOA: standard.2010.05.14

"The FBI is now conducting further forensic examination for the purpose of identifying trace evidence, residues and signatures of production that could provide evidence to support the investigation, " the agency said.

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"The FBI is now conducting further forensic examination for the purpose of identifying trace evidence, residues and signatures of production that could provide evidence to support the investigation, " she said in a news release.

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To qualify for the reward, claimants had to have contacted law enforcement and provide information that furthered the investigation and led to capture.

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