Police investigating 13 after cannabis raids

Police are investigating 13 people after raids on cannabis plots in Nelson , which have revealed some crops are flourishing while others have been hindered by possums and a lack of rain.

About 5000 plants worth millions of dollars have been seized since police began using an Iroquois helicopter last Thursday to spot crops, The Nelson Mail reported.

"I haven't seen them that big in a few years," operation commander Sergeant Steve Savage told the newspaper.

The crop was protected with an electric fence, cyanide paste and possum or "gin" traps.

This was now standard practice among growers who didn't want wildlife interfering with their crops, he said.

Detective John Nicholls, of Motueka police, said about 40 plants were "decimated" by possums because a "lazy" Murchison grower had not protected his crops.

Another crop was found grown indoors under lamps -- a sign that growers were being forced indoors, he said.

The annual cannabis recovery project, dubbed Operation Emma this year, runs from September until April.

The best crops were found in Golden Bay. With its high sunshine hours and regular rain, it was well known for its ideal growing conditions, Mr Nicholls said.

Police were investigating 13 people who were expected to face prosecution.

The helicopter operation, which ended on Monday, involved seven members of the air force and up to 19 police at any one time.

- NZPA