Today’s lesson of colloquial expression
688. to pick off ひとりずつ遠方から狙い撃ちにする、
- this means to kill members of a group, one by one; especially at long distances
1. Snipers hid in the top floor of the building to pick off any enemy soldiers who might wander into the town.
2. The characters in the movie were picked off one at a time by the monster until only two characters were left alive at the end.