To block your Stolen/Lost mobile phone in Pakistan :-
On-line: Online Complaint Form at CPLC: http://www.cplc.org.pk/imei_form.php OR
Call CPLC (Citizen Police Liaison Committee) 021-35662222 Police (Rescue 15)15
PTA (Pakistan Telecom Authority) 800-25625
They will get some basic info along with the IMEI number of your lost mobile set. and will request all the mobile operators to block this IMEI on their networks.
OR Fax fax your complaint to CPLC at 021-35683336 OR Email you can also send an email to PTA at firstname.lastname@example.org
IMEI is a number which is unique to every GSM mobile phone. It is usually found printed on or underneath the phone's battery and warranty card.
IMEI of any set can also be found by dialing the sequence *#06# into the phone.
The IMEI number is used by the GSM network to identify valid devices and therefore can be used to stop a stolen phone from accessing the network.
For example, if a mobile phone is stolen, the owner can call Authorities and instruct them to "block" the phone using its IMEI number. This renders the phone useless, regardless of whether the phone's SIM is changed.