[driftdiver]

Preferred method is to bury it. You can also throw it in a river. If those aren’t available you can burn it.

[Cicero]

Preferred method is to bury it.

So I now hear. But I don't think that burying them was an option, if they contain notes and jottings from terrorists. Too easy to dig them back up and pass them along to intended recipients. Maybe they just should have got an Imam to supervise and ensure that things were done acceptably.