CHAN: Australian police have seized the world's largest haul of ecstasy tablets. Some four and a half tons of ecstasy tablets with a street value of almost half a billion dollars have been seized. Sixteen people have been arrested across Australia and more arrests are expected as raids continue in the Netherlands, Belgium and Italy. STORY: Fifteen million tablets of the banned amphetamine ecstasy were found in 3,000 cans of Italian tomatoes shipped into Melbourne more than a year ago. Australia's top police officer says customs agents replaced the pills with harmless look-a-likes and tracked the delivery. [Mick Keelty, Australian Federal Police]: "A tactical decision was made not to declare the fact that we had together seized and removed the possibility of 4.4 tonnes reaching the Australian streets and that gave us the time and the space to analyse and to investigate what did occur here." Federal police commissioner Mick Keelty says police pounced 12 months later, carrying out raids in Australia, Belgium, the Netherlands and Italy. Sixteen people have been arrested so far and more warrants are out. [Mick Keelty, Australian Federal Police]: "There had been 10,000 hours of surveillance deployed to this operation to find the perpetrators of this world's largest seizure and importation into our country.” Police haven't confirmed local reports that the syndicate had links to the Calabrian mafia and an outlawed biker gang. The ecstasy seized has a street value of 400 million dollars.