Cross border attacks in Sabah

The cross border attacks in Sabah are a series of cross border terrorist attacks perpetrated by Moro pirates from Mindanao, Philippines, in the state of Sabah, Malaysia, that began even before the British colonial period. Many civilians have died or suffered during these incidents, causing an increase in anti-Filipino sentiment among the native peoples of Sabah, especially after major attacks in 1985, 2000 and 2013. The attacks were more intense during the presidential terms of Diosdado Macapagal and Ferdinand Marcos, who supported irredentist claims to include eastern Sabah as part of the Philippines territory. In addition, recent infiltration and attacks by militants as well as uncontrolled human migration from Mindanao to Sabah has led to more unease sentiments among the local residents of Sabah, with around 78% of prison inmates that were caught in the state due to involvement in criminal activities and lawlessness issues mainly originating from the southern Philippines.

Prior to a large-scale military operation initiated by Philippine President Rodrigo Duterte to combat the rampant lawlessness in the southern Philippines since mid-2016, Malaysian security forces had been told to tighten its security and to ensure that terrorists do not attempt to flee prosecution by escaping to uninhabited areas. Sabahan leaders also ordered Malaysian security forces to "shoot on sight" any trespassers who continue to ignore laws despite repeated warnings and that those escaping militants be dealt with by the country's laws more effectively. Following the declaration of martial law in the neighbouring Philippines since 23 May 2017, Malaysian authorities increased their border security. Sabah Chief Minister Shafie Apdal also urged the Malaysian security forces to stop taking a defensive attitude and be offensive towards the rampant crimes perpetrated by southern Filipino criminals and terrorists that has disturbed peace in the state.

Various countries and territories such as Australia, Canada, China, France, Germany, Hong Kong, Ireland, Japan, New Zealand, Singapore, South Korea, Switzerland, Taiwan, United Kingdom, United States and Vietnam have raised a travel alert for their citizens to avoid the area in eastern Sabah.

Piracy has been a part of the Sultanate of Sulu's culture. During the expedition by the British ship HMS Dido in 1846, Captain Henry Keppel mentioned:

The most desperate and active pirates of the whole Indian Archipelago are the tribes of the Sooloo group of islands lying close to the north shore of Borneo.

— Captain Henry Keppel.

The Sulu islands were known for their "great slave market" with their islanders frequently attacking Borneo Island in search of slaves. In 1910, the neighbouring Celebes Islands was attacked by seven Moro pirates whom had crossed from Mindanao, and two Dutch traders were killed in the incident. Subsequent reports from the British government in North Borneo reported that Joloano Moros terrorised the inhabitants of North Borneo, looting small towns and killing many people. Although the British did a lot to combat piracy, an office of a British company was later raided by twelve Moro pirates in Kalabakan in July 1958. Another raid was done on the nearby township of Semporna on 29 March 1954. During the last years of British rule in North Borneo, both seafarers and coastal settlements suffered a high numbers of attacks from pirates who were believed to be mainly based on Tawi-Tawi. Between 1959 and 1962, 232 pirates attack were recorded by the British authorities in North Borneo, but these were thought to be underestimated as many attacks went unreported. The British North Borneo governor at the time, Roland Turnbull had requested the British to provide him with security forces from the Royal Navy and Royal Air Force but no aid was sent until a British newspaper, the Daily Telegraph embellished the report with an anti-Indonesian bias because of the Indonesia–Malaysia confrontation.

Regional migration flows within Southeast Asia are not a phenomenon restricted to current times. Social and cultural connections between Sabah, Mindanao and the Indonesian province of North Kalimantan have existed for centuries. The tradition of border crossing from the Philippine Sulu Archipelago to Sabah originated in the late 16th century. The first wave of this migration was linked to the Spanish colonialists who began pushing southwards toward the island provinces of Sulu and Tawi-Tawi from Manila, which was the administration centre of the Spanish during that time. The struggle for dominance between different ethnic groups and the Spanish in Mindanao led to increased immigration of Philippine Moro ethnic groups, mostly the Suluks and Bajaus to Sabah.