How do I kill the skeletons located in The Catacombs?

Solution 1:

There are two ways to kill the skeletons:

• Kill the Necromancer reviving them. There are several Necromancers located in the catacombs (See below screenshot) which are responsible for the skeletons coming back to life. If you kill a Necromancer the skeletons in his area will stop reviving after you kill them. The Necromancer will not re-spawn after you kill him.

  (image source: taken from this video):

• Another way to ensure the skeletons stay dead, regardless of whether or not the Necromancer is still alive, is to kill them using a Divine weapon.

Solution 2:

Lure them to a pit and kick them into pit. That will do the job.