Called my personal line. Gave them as many "No" or "not saying" answers as I reasonably could. Of course, there is little I can do about it as they are outside Europe. The missing country code on the caller ID was typical of these calls. Called at 18:44 UTC. They're going on the redlist!

numrerous calls from this pest to my home phone UK. no answer when picked up either

Had 2 of these calls in last few weeks - both times they hang up on me.

I have been called by this number several times a day recently - no one speaks.  I have called the number back - no-one speaks and I don't know if I have been charged for the call.  April 2010

Around 3:30pm UK time I missed a call from 00 213 537 1000.
No message.
Either this is Algeria - country code 213
or "Downtown" Los Angeles area code 213

This is the first time an overseas number has shown up on 1471.