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CAIRO, May 17 (Reuters) - Sudanese opposition leader Sadiq al-Mahdi was arrested in Khartoum on Saturday, his office manager told Reuters, days after the public prosecutor accused him of blaming the authorities for violence in the troubled Darfur region.
Al-Mahdi, a former prime minister in Sudan's last elected civilian government, is the head of the Umma Party, the most prominent party opposing President Omar Hassan al-Bashir, who ousted him in 1989.
"Two security officers came to al-Mahdi's office at 8:45 p.m. Sudanese time and arrested him without giving any reason," said Mohamed Zaki, al-Mahdi's personal assistant and office manager.
Al-Mahdi was expected to engage in a national dialogue with Bashir's government and other opposition leaders.
The dialogue, which Bashir had called for earlier this year, was expected to ease tension among Sudan's top political parties ahead of parliamentary and presidential polls due next year.
Violence has escalated in Darfur in the west in recent months. Opposition leaders have been accusing government forces of violence against civilians in the region.
Western diplomats and Sudanese security sources estimate that thousands have been killed in clashes between militias supporting and opposing the government there since March. (Reporting by Khalid Abdel Aziz; Writing by Shadia Nasralla and Yasmine Saleh; Editing by Michael Georgy and Alison Williams)