The divide between the Sunni and Shia communities in Pakistan became highly politicised in the 1980s, as each sought to institutionalise their particular branch of Islam. Militant groups claiming to represent both sides emerged to further the respective agendas. Organisations such as the Sunni Sipah-e-Sahaba Pakistan (SSP) and its armed wing, Lashkar-e-Jhangvi (LeJ); the Shia Tehrik-e-Jafria Pakistan (TJP) and its armed wing, Sipah-e-Muhammad Pakistan (SMP); as well as local affiliates of the Islamic State, also known as ISIS or ISIL, have been the most prominent in instigating inter-communal violence. Backed by foreign funding and popular support, these groups have consistently attacked leaders, individuals and communities of the rival branch with limited response from the government. Sectarian violence has increased in recent years, as transnational networks of extremist groups encourage and become involved in the conflict. The rise of ISIS in 2013–14 and the group’s subsequent declaration of a caliphate has inspired a host of violence against Shia communities in Pakistan, including an attack on a bus in Karachi in May 2015 that left 43 Shi’ites dead.