The fighting started when a bomb exploded in an Indonesian border police patrol tower on November 7, 2008, killing four Indonesian border police and injuring two soldiers. Afterwards, two Indonesian patrol officers were shot by Malaysian snipers. The Indonesian armed personnel, as well as troops were given orders to open fire on the Malaysian side, and likewise. The Malaysian army claimed that the Indonesians were trespassing into Malaysian border, but the Indonesians claimed that the officers were within Indonesian territory in close proximity to Malaysia's border.
After a series of more border clashes, Indonesia officially declared war on Malaysia on November 12, 2008, thus starting the four-year long Borneo War.
Timeline of events
November 7, 2008 - A bomb explodes at the Indonesian border patrol in North Kalimantan near Malaysia's southern borders at an officer patrol tower, four Indonesian border officers are killed, a soldier is injured. Two more Indonesian officers are shot by Malaysian snipers. The Indonesians order their policy and army personnel to open fire at the Malaysians. One Malaysian border officer is killed, three are injured.
November 8, 2008 - The Indonesian government demands explanation from Malaysia for their "act of aggression". Indonesian intelligence points that bomb was not made in Indonesia, and that the Malaysians illegally shot two border officers within Indonesia territory. However, the Malaysian government refutes claims of any involvement in the bombing, Abdul-Halim the Sultan of Kedah expresses his condolences for the Indonesian officers killed the bombing. Malaysian intelligence also argues that the Indonesian officers shot were trespassing into Sabah illegally. Indonesia demands $500,000 from the Malaysian government in damage costs.
November 9, 2008 - The Malaysian government only offers to pay $200,000 for the damage costs, only offering the reason that they want to maintain peaceful relations with Indonesia and that Indonesia is an important ASEAN strategic partner. However, the Indonesian government rejects the offer, stating that they wanted a full $500,000. As a result, Indonesian mortar squads fire into Malaysia, destroying three patrol towers, killing two Malaysian border troops and injuring one.
November 10, 2008 - The Royal Malaysian Air Force sends two Sikorsky S-70 Black Hawks, heavily damaging Indonesian armored vehicles. Five Indonesian border officers are killed in the attack, as well as the destruction of three military officer buildings. Malaysian prime minister Abdullah Badawi states that the Indonesians need to give peace a chance, and that Malaysia will use military force to subdue Indonesia into doing so if they must. Indonesian and Malaysian governments continue back and forth arguments.
November 11, 2008 - Indonesian and Malaysian militaries halt all activities, though no ceasefire was signed.
November 12, 2008 - Indonesia declares war on Malaysia, Indonesia sends bomb squads to de-activate Malaysian mine fields
November 13, 2008 - Malaysian armored divisions begin to enter northern Indonesia, the Indonesian Air Force sends warplane to carpet-bomb the tanks. Two Indonesian planes are shot down by AAs