They're called sowbugs here in the U.S. Usually, they are helpful additions to garden areas since they eat and break down dead plant material. But, if they atart on your ripening tomatoes, game over. They are easily controlled however, with various chemical sprays. I'm averse to using chemicals on ripe produce but have found a product called "Sluggo" or even bettter, Sluggo-Plus" is an organic product and works very well. It's spread around the plant area but hs to be re-applied in the event of rain or sprinkler applied watering.
If this isn't available by name, look for any pest control with iron phosphate as the active ingredient. It's totally organic and inexpensive...