Bernie McClenny, W3UR and editor of The Daily DX newsletter says that for more than a year an Amateur Radio operator from Southern Europe has been pirating calls on CW.
It started off with VU2TS, but only on CW. Then he was switching between VU2TS and 4U1ITU, when the club was using 4U1WRC, again CW only. Then he began using 5H3PM, CW only and now the pirate has switched over to 5H3MG again - CW only.
Bernie says he has confirmed with Tanzania Communications Regulatory Authority (TCRA) that both 5H3 calls are not currently registered calls. The signals are clearly coming from Southern Europe. You can see his typical operating pattern here. It should be noted that QSL cards for 4U1ITU can only legitimately be confirmed by the club.