Papamoa locals have been left scratching their heads after a dozen mystery pineapples washed up in the surf.

The tropical fruits were scattered along the shoreline near Karewa Parade last night.

While many locals investigated, they said the smell put them off taking them home for pina coladas.

Local resident Chase Schiphorst says the pineapples were near Karewa Parade and spread across a 30m stretch of the beach.

Chase says it was possible a container ship or barge had dropped them, but after hearing that cocaine had been hidden inside fresh pineapples in Europe, he wondered whether there was a bigger story at play.

The Ministry for Primary Industries says it doesn't believe the pineapples are likely to present a biosecurity risk as they have to be treated for pests and insects before being exported to New Zealand.

The fruit would also have been thoroughly fumigated if it had been at sea for some time.

If anyone has concerns with the pineapples, they are encouraged to phone the ministry's biosecurity number on 0800 80 99 66.