The cargo would leave the next morning at 2 AM; no one at that time would be alert.

第二天早上淩晨两点，重型卡车就会离开，那个时候没有人会发现。

youdao

But it was comforting to know, we got an announcement on our plane that there had been a security alert at Heathrow, but no one told us precisely what that would mean.

NPR: The Scene at London's Heathrow Airport

No Amber Alert was issued the day DeJesus failed to return home from school in April 2004 because no one witnessed her abduction.

NPR: 3 Missing Women Found In Ohio, 3 Brothers Arrested