KHARTOUM, Sudan — Sudan’s first multiparty elections in decades have been thrown into disarray by allegations of government violations and opposition threats of a boycott. The disputes wreck hopes of transforming a conflict-plagued nation and could instead end up fueling violence in Darfur and the south.

The election, due to begin April 11, had been billed as a chance to bring democracy to Sudan and start to heal a history of turmoil: 50 years of civil war between north and south that killed 2 million people, repeated military coups, and years of violence in the western Darfur region that the United States called the 21st century’s first genocide and that brought international war crimes charges against the president, Omar al-Bashir.

The United States and other nations have invested heavily in the elections, which are required under a 2005 peace deal between north and south mediated by Washington.

But experts say the elections are likely to be deeply flawed and won’t resolve the deep mistrust between the multiple sides — leaving divisions that could once again re-ignite into violence.

Many in the south are already looking forward to a more crucial vote next year: a referendum on independence for their oil-rich region. But many fear the north will do anything to prevent the referendum from being held, which could bring the two sides again to the brink of war.

The mainly Christian and animist south fought for decades against rule by the mainly Muslim north. The separate conflict in the western region of Darfur erupted in 2003, when ethnic African tribes rose up complaining of discrimination by the Arab-led government in Khartoum.

The theory behind this month’s local, parliamentary and presidential elections has been that they would loosen al-Bashir’s autocratic control and decentralize power to address the factors that fueled conflicts in Africa’s largest nation ahead of the crucial referendum.