"QRZ WCC..."

Around the end of the 1970's I had the 500 kHz watch on Norddeich Radio.  It was around 2:00 or 3:00 am, the traffic list had already been sent, the North Sea and English Channel traffic had quieted, and one could hear ships and coast stations in the Mediterranean Sea and North Atlantic.  Things were getting cozy, and one could lean back in one's chair and drink coffee.
Suddenly a loud and persistent call on 500 kHz!  The callsign was, to the best of my memory, "HPZZ".
The call went: OXZ DE HPZZ QRU? K  (Lyngby Radio from HPZZ; have you anything for me?)  The answer was "HPZZ DE OXZ NIL" (We have nothing for you)
It went again: GKZ DE HPZZ QRU? (Humber Radio, also nil), then OST DE HPZZ QRU? (Ostende Radio - also nil), then PCH DE HPZZ QRU? (Scheveningen Radio - also nil), then GNI de HPZZ QRU? (Niton Radio - also nil).
Meanwhile, someone at a radio station was very annoyed, and shortly we heard "MIM."  This is a non-official abbreviation for an insult which cannot be described here.  My colleagues on night service heard it over the loudspeaker and grinned.
And so it came to us: DAN DE HPZZ PSE QRU?  Before I could answer, one of  my colleague called and said that he would communicate something to the ship.   OK I answered, and sent; HPZZ DE DAN PSE UP 425/474.  (HPZZ from Norddeich Radio, please send on 425 kHZ and listen on 474 kHz.)  Then traffic on the working frequency would logically follow.  After about three minutes my colleague stood up and said "Now we're having peace and quiet in the North Sea.  We won't be hearing HPZZ on 500 kHz again." We were curious and would like to know what the ship had to say.
I heard him transmit: QRZ WCC MSG FER U. (Note that WCC, Chatham Radio, is the largest American coastal station on the east coast of the USA, next to New York.  The text means that he has a telegram for WCC.)
And what did the ship have to say?  We would like to know.  I acknowledged with a nod of my head, and said to my colleague, "You are not as imbecilic as you seem."
Then again a loud call on 500 kHz, and it went; WCC WCC DE HPZZ PSE QRU?
Then there was a momentary pause on the air, and a Radio Inferno broke loose on the poor radio operator on HPZZ such that I have seldom seen.  The comments and insults that the poor fellow heard I do not exactly with luck remember.  It continued for a while, and the North Sea and English Channel once again became quiet.
Who was guilty?  Naturally Norddeich Radio, but I repented quietly on 500 kHz.  With luck we would not hear from HPZZ...