CrPC Section 69
Service of summons on witness by post
1. Notwithstanding anything contained in the preceding section of this Chapter, a Court issuing a summons to a witness may, in addition to and simultaneously with the issue of such summons, direct a copy of the summons to be served by registered post addressed to the witness at the place where he ordinarily resides or carries on business or personally works for gain.
2. When an acknowledgment purporting to be signed by the witness or an endorsement purporting to be made by a postal employee that the witness refused to take delivery of the summons has been received, the Court issuing the summons may declare that the summons has been duly served.