 Due to the losses his brigade suffered on 16 June , Porter decided to continue the bombardment before undertaking further attacks . On 18 and 19 June the bombardment of the Pocket was intensified when the heavy cruiser HMAS Shropshire fired into the area . Infantrymen supported by tanks conducted another probe into the Pocket on 19 June , and killed 10 Japanese ; three Australians were wounded . On 20 June the 2 / 12th Field Regiment fired a particularly heavy bombardment and six Allied bombers attacked the Pocket . Porter judged that this would be sufficient to suppress the Japanese defenders , and ordered that the Pocket be attacked by two companies from the 2 / 28th Battalion supported by tanks ( including " Frog " flamethrower variants of the Matilda II ) the next day . 
