Complex sentence: The group also protested the carrying of new "white and blue banners with two inverted triangles in the middle", drawing the attention of the British authorities to the serious consequences of any political implications in raising the banners.
Split into simpler sentences: The group also protested the carrying of new "white and blue banners with two inverted triangles in the middle". They drew the attention of the authorities to the serious consequences of any political implications in raising the banners.