Numbers 10:6

And when you blow an alarm the second time, then the camps that are located on the south side must begin to travel. ¹  An alarm must be sounded ²  for their journeys.

Nu 2:10-16

¹ tc The MT does not mention the departures of the northerly and westerly tribes. The Greek text completes the description by adding them, making a full schedule of the departure of the groups of tribes. The Greek is not likely to be original, however, since it carries all the signs of addition to complete the text, making a smooth, full reading. The MT is to be preferred; it apparently used two of the groups to give the idea.

² tn The Hebrew text has “they shall blow an alarm”; the sentence without a formal subject should be taken as a passive idea.