What happens with society in Lord of the Flies?

During his attempt to hunt down and kill Ralph Jack sets fire to the island. The plume of smoke attracts the attention of a ship. When Ralph breaks free from the jungle and staggers onto the beach, pursued by Jack and his tribe, he almost runs into a naval officer. When the officer asks whether the boys are playing war and adds that he hopes that nobody has been killed. Ralph breaks down in tears and tells him, "Only two."