Airtel and tataindicom
Untimely calls

I am getting calls from 020-40152900 and 020-67245700 at odd hours and as soon as i pick up the phone it is disconnected. I tried to ring up these numbers but there is no response. I get a feeling that these numbers are being used to harass people and the tele companies have given these phones to criminals, who are trying to find out if i am at home or not. I got no response from airtel or tata-indicom people in pune.