I received a call from this number from a person posing as a relative which I did not recognized. I figures out that he was trying to find if someone was at home.

The FTC warns about the family emergency scam here http://www.ftc.gov/bcp/edu/pubs/consumer/alerts/alt111.pdf  Report to the Internet Crime Complaint Center http://www.ic3.gov/complaint/default.aspx , the Federal Communications Commission http://esupport.fcc.gov/complaints.htm , the Federal Trade Commission https://www.ftccomplaintassistant.gov/ and your state AG http://www.naag.org/current-attorneys-general.php as appropriate.