Civilians then checked IDs again, fearing plain-clothes police might seek to act as agents provocateurs.

平民们接着再次检查身份，唯恐可能混入便衣警察伪装的奸细。

youdao

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

Hostilities broke out last month when bulldozers, accompanied by armour-clad police and plain-clothes thugs, entered Rechnik at 4am.

双方敌对情绪于上月爆发，开始时推土机、顶盔贯甲的警察及衣着平常的恶徒在凌晨四时浩浩荡荡进驻里芝柯。

youdao

When Kiddell, posing as Mr Russell, turned up for an appointment he was arrested by plain clothes police.

BBC: Brian Kiddell

An undisclosed number of plain clothes police officers are travelling to Germany to help identify offenders who slip through the net.

BBC: England fans barred from Germany

Miners say plain clothes police have infiltrated picket lines and officers have also been turning away pickets thought likely to cause a breach of the peace.

BBC: 1984: Dozens arrested in picket line violence