General Muhammad Zia-ul-Haq enforced martial law for the third time in Pakistan's history after overthrowing Prime Minister Zulfiqar Ali Bhutto's government in a 1977 coup. Zia promised to hold elections within 90 days but later postponed them and started an accountability process against politicians. Zia assumed the presidency in 1978 and introduced an advisory body called Majlis-e-Shoora while remaining the ultimate authority. Zia was elected president in a 1984 referendum and held non-party elections in 1985, increasing his powers through a constitutional amendment. Zia dissolved the national assembly and removed the prime minister in 1988, promising again to hold elections, but died in a plane crash before doing so.