(ANSA) - ROME, MAR 12 - Hundreds of empty bottles of ketchup and full bottles of mayonnaise are washing up on the shores of Puglia's picturesque Salento coast, the head of an Italian plastic pollution awareness-raising project said Sunday.
    Both set of bottles are of American origin and it is not yet known how they ended up in the sea.
    The riddle was reported by 'Archeoplastica' Project founder Enzo Suma, who about a year ago reported the arrival by sea of many packages of preserves from Albania.
    The empty ketchup bottles have come in two waves, the first being made up of larger bottles and the second of smaller ones.
    They have been hitting mostly the beaches of Lecce and Gallipoli, but a few dozen have also reached the Brindisi shoreline.
    The most likely explanation is that they were lost by a US ship somewhere in the Adriatic or Aegean, Suma said. (ANSA).