I was clear that I didn't want to make an official report. But he called in two other officers, opened a case file and started an investigation.

我清楚自己并不想做一个正式的报告，但他却叫了另外两个警官近来，打开文件夹开始了问询。

youdao

We have put the homicide case on file for investigation and prosecution.

这起他伤致命的案子我们已经立案调查了。

youdao

Using retain should be front of placing a case on file for investigation or prosecution of public security and crime.

留置的使用在治安立案和刑事立案之前，传唤和拘传使用于立案之后。

youdao

He say the government plans to file a court case against Sufi Mohammad after conducting a detailed investigation into his extremist activities.

VOA: standard.2009.07.26

After an investigation, the district attorney declined to file felony charges in the case and referred it to the city attorney, who filed the misdemeanor charges.

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