The fort became known as the Negro Fort and considered a serious threat to the United States. In response, Major General Andrew Jackson ordered a fort, called Fort Scott, to be constructed upriver from Negro Fort for the purpose of attacking the stronghold. On July 27, 1816, the Americans attacked. A cannonball struck the magazine, causing an enormous explosion that killed 300 people including women and children. Only 33 survived and were forced back into slavery.
Recognizing the strategic importance of the site, Andrew Jackson ordered a Lieutenant named James Gadsden to build the second fort in 1818. Soldiers were stationed there until Spain ceded Florida to the United States in 1821.
Some considered General Andrew Jackson's expedition of 1818 as treasonous. Congress did not grant him permission to act and used border incidents as justification to attack Negro Fort. While following the river, he destroyed more than just this fort. He also attacked Indian strongholds while moving down the river. He also captured two British soldiers that he eventually executed. These incidents cause an uproar in the Congress and the Cabinet but all of this died down shortly after Florida became part of the country.