Unbeknownst to the Kedah Sultan, however, Light had acted without the authority or consent of his superiors in India. When Light reneged on his promise of British military protection against Siam, the Kedah Sultan in 1791 assembled an army in what is now Seberang Perai to retake the Prince of Wales Island. The Sultan's force was also assisted by a fleet of pirates. Fortunately for Light, his garrison on the island was reinforced by two companies from Calcutta. After failing to persuade the Sultan to disband his forces, the British East India Company launched amphibious assaults at night, destroying Kedah's military installations in Perai, and defeating both the pirates and the Sultan's army.