If it sounded like superfast, sloppy or drunk sounding, non-stop CW with UNID characters it was probably Russian FSK, 7 kHz apart, and it will shift both frequencies every 20-30 minutes or so.
There are other threads on HFU about this. I've heard this maybe 10-12 times over the past year -- in the lower part of the 40 Meter Ham band (usually between 7010 and 7070) and also below the 40 Meter ham band (usually above 6900 kHz).
Haven't heard it in two or three months, probably because of mediocre band conditions.
The closest location for the transmitter that anyone can figure out is either Crimea somewhere, or the Caucasus.