12-metre humpback whale strands in Firth of Thames

A 12-metre long humpback whale has died overnight after stranding in the Firth of Thames.

The Department of Conservation (DoC) says the whale died around midnight on Thursday night after locals found it alive near Kaiaua earlier in the evening.

A DoC response team was on site before 9pm, joined by iwi and local volunteers including a member of the fire brigade who tried to keep the whale comfortable.

Iwi and locals have been working with DoC on plans to bury the whale.

Local man Brett Spicer told Newshub he was amazed by the animal's size.

DoC Hauraki operations manager Avi Holzapfel praised the team who stayed with the whale overnight.

The cause of death is not yet known, nor why the whale swum so far up the Firth of Thames. Samples have been taken for genetics, toxicology, and stable isotope analysis.

Newshub.