Police have stopped a major haul of 'skunk' marijuana reaching the Italian streets.

Police pulled over a truck travelling from Belgium at the Mt Blanc tunnel and uncovered 15kg of skunk with a street value of almost one million euros.

It was one of the largest ever hauls in Italy of the new, stronger strain of marijuana.

Police arrested the truck driver, an Italian, and his Moroccan co-driver.

Skunk is specially grown to boost the active ingredient so that the marijuana is up to four times stronger than a few years ago.

Some experts say it can cause psychosis and, in the long term, even schizophrenia.