They came in a huge truck full of police men, plus two police women, plus a plain clothes intelligence agent and a magistrate.

他们开来了一辆很大的卡车，里满全是警察，其中有两名女警。

youdao

KGB officers in plain clothes were clearly in charge even at the police station, and the arrest itself was as choreographed as the trial to come.

很明显，当时是由克格勃的便衣警察在掌控局势，甚至在警署也是如此，逮捕行动和接下来审讯一样都是他们编排的。

youdao

Palestinian police in the designated area patrol in plain clothes and unarmed, but are not allowed to use force to restrain the settlers if they seek to impose themselves on the Palestinian villagers either by attacking them or by damaging their property.

ECONOMIST: The West Bank

Plain-clothes police lurk everywhere in Lhasa and the towns.

CNN: From Our Correspondent: Far Braver Than I

One group recently attacked several stallholders at an open-air market in Rafina, a port near Athens, after posing as plain-clothes police checking their permits.

ECONOMIST: Greek politics