evidence: Bahrain and Qatar [edit]Starting in 1936, Qatar and Bahrain were involved in territorial disputes over the Hawar Islands, Fasht Al Azm, Fasht Dibal, Qit'at Jaradah, and Zubarah. The most substantial dispute was the Fasht Dibal conflict in 1985, after Bahrain began constructing fortifications on the island. Qatar considered the construction to be a violation of an existing agreement made in 1978.[4] In April 1986, Qatari troops arrived on the island via helicopter and declared it a 'restricted zone'. They seized several Bahraini officials and 29 construction workers hired by the Dutch contracting company Ballast Nedam.[5][4] On 12 May 1986, following protests by the Netherlands and mediation by several GCC member states, Bahrain and Qatar reached a settlement, after which the foreign workers were released. Qatari troops evacuated the island on 15 June.[5]