Related Rule
New Zealand
Practice Relating to Rule 67. Inviolability of Parlementaires
New Zealand’s Military Manual (1992) provides: “A parlementaire and accompanying trumpeter, bugler, (or drummer), flag bearer and interpreter are all protected in the case of an authorised communication made under the protection of a white flag.” 
New Zealand, Military Manual (1992), Annex B, § B45; see also §§ 638 and 718 (protection of cartel ships).
The manual specifies:
The belligerent to whom a parlementaire is being despatched does not have to cease combat, although he may not fire upon the parlementaire, his flag or those with him. Since the adverse Party may continue combat, the parlementaire should cross during a lull in the fighting or should seek some other moment for making his journey, or travel by a route that reduces any risk to himself or those with him. The parlementaire and those with him are entitled to complete inviolability, so long as they do nothing to abuse this protection or to take advantage of their protected position …
To fire intentionally upon the white flag carried by a parlementaire is a war crime … No offence is committed if the parlementaire or those with him are injured accidentally, or even if the white flag he carries is fired upon inadvertently …
During the period that the parlementaire is conducting his negotiations the conflict continues and both sides are entitled to reinforce or take such other combat actions as they consider necessary … During his withdrawal and return to his own lines, the parlementaire continues to enjoy inviolability and may not be attacked. 
New Zealand, Interim Law of Armed Conflict Manual, DM 112, New Zealand Defence Force, Headquarters, Directorate of Legal Services, Wellington, November 1992, § 406(3), (4) and (6); see also Annex B, §§ B44 and B45.