This is most likely the infamous "Indonesian Chanters" that appear frequently on 7000 khz, 6995 khz, 6990 khz, 6985 khz, etc. LSB. I hear them often e.g. four days out of seven on several frequencies most mornings here (100 miles from the Pacific Ocean) from 1500 utc. until they fade out by ca. 1700 utc. Seems to be some sorta Village Radio-type thing. Usually, such loggings end up on the "Peskies" board, that is where I (and others) have been occasionally posting them. Sometimes they engage in routine-sounding QSOs (not so eerie) but when they repeat a phrase / chant in "call-and-response" mode, it sounds rather quite eerie!
Osborne White, Engineer
Radio Mysterious Mystic Radio / WMMR