Sudan severed relations with Chad on Sunday, accusing it of supporting fighters who assaulted the capital the night before, and warned that a top Darfur rebel leader was hiding somewhere in the city. A curfew was lifted in Khartoum but remained in effect in the capital's twin city of Omdurman, where rebels were still loose, state-run radio reported quoting police Maj. Gen. Mohamed Abdul-Majeed. The country's official news agency said more than 300 rebels were arrested Sunday across Omdurman. The surprise assault late Saturday was the closest Darfur rebels have ever come to Sudan's seat of government, hundreds of kilometers (miles) from their bases in the far west of the country. The government issued several statements claiming to have crushed the rebels and paraded images of captured and bloodied fighters on television. State media said 50 rebel trucks were seized in Omdurman and a neighboring village.