The undercover police officers told residents they were screening for high blood pressure and handed out pills.

警察医生“称他们来调查高血压情况，并且还分发药片给居民。”

youdao

The operation followed months of undercover police work that gathered evidence of an extraordinarily lucrative empire.

经过数月的秘密工作，收集了这个非常有利可图的团伙的证据之后，警察展开了这次行动。

youdao

The evidence obtained by undercover police officers beyond the legal authority should be evaluated by effective ways.

卧底警察超越法律授权的范围获得的证据是否有效应从多方面进行评价。

youdao

In addition to the Italians, British and Spanish police officers will be on patrol in uniform and undercover.

VOA: standard.2009.05.26

Undercover police in Hard Rock Cafe T-shirts escorted two people off the dance floor.

CNN: IN THE GRIP OF ECSTASY

He said known English hooligans had been stopped from travelling and undercover police officers were in Moscow to try to spot any other troublemakers.

BBC: So far, so peaceful in Moscow

We were caught up in English supporters chasing after undercover police.

BBC