Indonesia–Malaysia border crossings. Illegal immigrants are also known to use such crossings. There are numerous scheduled sea crossings between Indonesia and Malaysia, mostly between ports in the former's island of Sumatra and Peninsula Malaysia. Here is a list of ports (Indonesian port followed by the Malaysian port) where scheduled boat services operate as of April 2008: Sumatra-Peninsula Malaysia North Kalimantan-Sabah Indonesia–Malaysia border The border between the Southeast Asian countries of Indonesia and Malaysia consist of both a land border separating the two countries' territories on the island of Borneo as well as maritime boundaries along the length of the Straits of Malacca,
Brunei–Malaysia border Petronas Carigali Sdn Bhd and US-based Murphy Sabah Oil Co. Ltd for two areas, which Malaysia calls Block L and Block M, which lie exactly within the area claimed by Brunei as part of its continental shelf/EEZ. Later in March 2003, a Bruneian gunboat was sent to drive away a Murphy drilling ship in the area. The following month, the Malaysian navy sent several gunboats into the disputed area to block the arrival of a Total ship. After a tense stand-off involving a single patrol craft from Brunei, Total backed off and both sides stopped work in the disputed areas.