Yep...sounds like necromancy to me. Expressly forbidden in the Bible (Deut. 18:10-12).
Remember that King Saul sought the spirit of the long-dead Samuel. Didn’t turn out quite the way Saul intended, did it (1 Chron. 10:13)?
We need to be casting out demons in the name of Christ on our streets and at these coven rituals.