The Five Power Defence Arrangements is a regional security initiative which has been in place for almost 40 years. It involves joint military exercises held among Malaysia, Singapore, Australia, New Zealand, and the United Kingdom. Joint exercises and war games have also been held with Brunei, China, India, Indonesia, Japan, and the United States. Malaysia, Philippines, Thailand, and Vietnam have agreed to host joint security force exercises to secure their maritime border and tackle issues such as illegal immigration, piracy, and smuggling. Previously there were fears that extremist militants activities in the Muslim areas of the southern Philippines and southern Thailand would spill over into Malaysia. Because of this, Malaysia began to increase its border security.