Pannai was a militant nation allied under the empire-mandala of the Srivijaya that defended the conflict-ridden Strait of Malacca. The small kingdom repulsed any unlicensed Chinese, Indian or Arab navies that often warred in or pirated the straits of Malacca and for a small nation, they were adept at taking down armadas larger than itself. They were successful in policing and defending the straights of Malacca for the Srivijaya until the Chola invasion of Srivijaya occurred, where in a surprise attack from behind, originating from the occupied capital, rendered the militant-state of Pannai vulnerable from an unprotected assault from the back flank. The Chola invaders eventually destroyed the state of Pannai and its surviving soldiers, royals and scholars were said to have been secreted-out eastwards. The high-borne scholars, soldiers and nobles of Pannai, "fled to other islands." Some of whom, now known as Suludnon, settled (and the named the island after Panni) in Panay island in Visayas in Philippines. Some historians also affirm the Sumatran origin of the people of Panay, observing that the Visayans derived their writing system from those of Toba, Borneo, Celebes, Ancient Java and from the Edicts of the ancient Indian emperor Ashoka. The very probable proof of Sumatran origin of the Malay settlement in Panay is the account of P. Francisco Colin, S.J, a historian who came to Asia during the early years of the Spanish conquest of the Philippines. The following is his personal observation recorded during his visit to Sumatra: