My mom just called me in regards to this as well and she stated that she has received several calls from this number 213-948-1400.  I tried calling and I got voice-mail.  I was hoping to get a live person.

She told me that she tried calling the number back and got some one but the person on the other side said that it was not him who had called and that his number ended in 1401 and not 1400.  But my mom checked and made sure she dialed the right number.

I've advised my mom to file a police report under "harrassing" phone calls if it continues.