Warning: distressing images. An adult humpback whale that got stranded on a sandbar at Dunedin's Blueskin Bay suffered significant injuries and later died, Doc says.

"I just want to get all my affairs in order before I snuff it," one handwritten note read.

Conservation groups and about 30 locals have gathered in Blueskin Bay as a humpback whale tries to free itself from a sandbar.

Dame Jacinda Ardern has called the war in Gaza a "genocide", joining a growing chorus of international experts, world leaders and organisations saying Israel's actions meet the definition under international law.