Complex sentence: At midnight on the 28th the armada ran into the minefields while being attacked by Finnish and German torpedo boats; casualties were heavy, 65 of the 160 ships were lost, and several more were damaged.
Split into simpler sentences: At midnight on the 28th the armada ran into the minefields while being attacked by Finnish and German torpedo boats. Casualties were heavy, with 65 of the 160 ships lost, and several more were damaged.