Reply #80: Sorry, I cited it wrong. Here you go: [View All]

Convention (II) for the Amelioration of the Condition of Wounded, Sick and Shipwrecked Members of Armed Forces at Sea. Geneva, 12 August 1949.

Chapter II : Wounded, sick and shipwrecked

Article 20

Parties to the conflict shall ensure that burial at sea of the dead, carried out individually as far as circumstances permit, is preceded by a careful examination, if possible by a medical examination, of the bodies, with a view to confirming death, establishing identity and enabling a report to be made. Where a double identity disc is used, one half of the disc should remain on the body.
If dead persons are landed, the provisions of the Geneva Convention for the Amelioration of the Condition of the Wounded and Sick in Armed Forces in the Field of August 12, 1949, shall be applicable.

http://www.icrc.org/ihl.nsf/COM/370-580024?OpenDocument


The only real murkiness lays in that last sentence. Technically, if the body was taken back to land, they would have been required to bury it. Because the body was taken to sea, they didn't have to. It's certainly a loophole, but what they did is entirely legal under international law.