As dawn approached, lookouts on HMS "Lively", a 20-gun sloop of war noticed the activity and the sloop opened fire on the rebels and the works in progress. This in turn drew the attention of the British admiral, who demanded to know what the "Lively" was shooting at. Subsequent to that, the entire British squadron opened fire. As dawn broke on June 17 the British could clearly see hastily constructed fortifications on Breed's Hill, and British Gen. Thomas Gage knew that he would have to drive the rebels out before fortifications were complete. He ordered Major General William Howe to prepare to land his troops. Thus began the Battle of Bunker Hill. American Col. William Prescott held the hill throughout the intense initial bombardment with only a few hundred American militia. Prescott knew that he was sorely outgunned and outnumbered. He sent a desperate request for reinforcements.