A trust that was trying to preserve an historic Auckland ferry that sank last week has asked police to investigate film footage that may show what caused the mystery sinking.
The Kestrel, which plied between Auckland and Devonport from 1905 to 2002, sank at its mooring at Wynyard Wharf overnight on Monday last week.
Kestrel Preservation Society chairman Mike Alston said the vessel had a float-switch alarm that should have sent texts to two people as soon as any water got in.
"The strange thing from our point of view is that the alarm never sounded," Mr Alston said.
"There were organisations, including commercial organisations, that wanted us moved because it [the boat] was just in their way.