Sudan's Islamist leader Hassan al-Turabi has been freed from custody hours after being arrested following a rebel raid near the capital, Khartoum.
He was arrested early on Monday by soldiers, who accused him of links to the rebels, his wife Sudan cuts Chad ties after Darfur rebel attack ...
Chad 'orphans' to return to homes ... told the BBC.
He has denied previous such claims, although some Darfur rebel leaders have followed him in the past.
The authorities continued to hunt for suspected rebels on Monday following the surprise weekend attack.
The raid by the Justice and Equality Movement (Jem) on Omdurman, Khartoum's twin city, across the River Nile, was the closest they had come to the capital in five years of conflict in Darfur.
The BBC's Amber Henshaw in Khartoum says there was panic in the city centre, when security agents opened fire at a small group of people hiding in a building and sealed off several streets.
Interrogated
The curfew was reimposed in Omdurman on Monday.
Sudan has blamed the attack on neighbouring Chad, which has denied any links, as has Jem.
The government says it has repulsed the attack but Jem leader Khalil Ibrahim says they will be back.
"This is just the start of a process and the end is the termination of this regime," he told Reuters news agency.
Mr Ibrahim used to follow Mr Turabi and correspondents say they share an Islamist ideology.
Our correspondent says Mr Turabi was interrogated for several hours by the security forces over the weekend attack.
She says it appears that he has not been charged.
The Sudanese government says it has learned lessons from the attack and will be better prepared next time.
Sudan's ambassador to the UN, Abdalmahmood Abdalhaleem, told the BBC that captured rebels had identified Chadian officers killed during the assault.
Sudan has severed diplomatic ties with Chad.
Mr Turabi was Sudan's main Islamist ideologue in the 1990s before falling out with President Omar al-Bashir. He has since been imprisoned several times.
Experts say Chad and Sudan are fighting a proxy war using each other's rebels to achieve their military objectives.
Earlier this year, rebels reached Chad's capital N'Djamena, with Chad accusing Sudan of involvement.
(BBC)
<< Back