China set off alarm bells in New Zealand when it dispatched powerful warships on unprecedented missions in the South Pacific without explanation, according to military documents obtained by AFP.

Beijing has spent years expanding its reach in the southern Pacific Ocean, courting island nations with new hospitals, freshly paved roads and generous offers of climate aid.

But these diplomatic efforts have increasingly been accompanied by more overt displays of military power.

Three Chinese warships sailed the Tasman Sea between Australia and New Zealand in February this year, the first time such a task group had been sighted in those waters.

"We have never seen vessels with this capability so close to our shores -- ships equipped for air, land and sea warfare," New Zealand Defence Force off

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