Notice under Section 160 CrPc to accused

As many time and as and when the requirement arise. As such there is no limitation or restriction.

^In other words, as long as it takes for the police to complete the investigation, they can call in any witnesses who they think is acquainted with the facts and circumstances of the case. In my assumption, it would be till the filing of the chargesheet, (after which, the inquiry/trial are to finally begin.)