By Khalid Abdelaziz and Ulf Laessing
KHARTOUM (Reuters) - Rebels from Sudan's Darfur region launched a dawn attack on the city of Um Rawaba on Saturday, taking their fight closer to the capital Khartoum, witnesses said.
The attack marks the biggest push by a rebel alliance that is seeking to topple President Omar Hassan al-Bashir. Fighting had hitherto been limited mainly to remote regions of Darfur and South Kordofan and Blue Nile states, which border South Sudan.
The Justice and Equality Movement (JEM), which launched an unprecedented assault on Khartoum in 2008, said the rebel alliance stormed Um Rawaba in North Kordofan state, around 500 km (300 miles) south of the capital.
Sudan's army said late in the evening it had restored security in the state's second largest city. It accused insurgents of destroying a power plant, petrol stations and a telecommunications tower.
"The defeated rebels have withdrawn, and the army is continuing to expel elements of the rebels who have run away in different directions," army spokesman al-Sawarmi Khalid told state news agency SUNA.
JEM spokesman Gibril Adam said forces from the group had only withdrawn from the center of Um Rawaba to the outskirts after Sudanese warplanes had launched air strikes.
The rebels arrived at dawn with 20 trucks in Um Rawaba, an important market for a major Sudanese agricultural export product, gum arabic, residents said.
"People are in a state of panic," said one Um Rawaba resident, asking not to be named.
The rebels then opened fire into the air and looted a market and several commercial banks. JEM's spokesman denied any pillaging by rebels.
"The goal of this attack is to weaken the government to realize our strategic plan to topple the regime," JEM spokesman Adam said.
The government later said it had reopened the key road between Khartoum and the North Kordofan state capital El-Obeid, which had been blocked by fighting, state governor Mutassim Mirghani Zaki Uddi told the state-linked Sudanese Media Center.
On a separate front, the SPLM-North which is part of the rebel movement attacking Um Rawaba, said it had seized four villages east of Kadugli, capital of South Kordofan state. There was no immediate comment from the army on the statement.
Events outside Khartoum are difficult to verify in the vast African country. Um Rawaba is a two-hour drive from Kosti, Sudan's biggest Nile river port.
JEM forces drove across hundreds of miles of desert to attack the Khartoum suburb of Omdurman in May 2008 and were stopped just short of the presidential palace and army headquarters.
The group was one of two main rebel forces that took up arms against Sudan's government in 2003, demanding better representation for Darfur and accusing Khartoum of neglecting its development.
Khartoum mobilized militias to crush the uprising, unleashing a campaign that Washington and activists described as genocide. Sudan's government denies the charge and accuses the Western media of exaggerating the conflict.
In 2011, JEM teamed up with two other Darfuri groups and the Sudan People's Liberation Movement-North (SPLM-North) which took up arms in South Kordofan and Blue Nile states around the time of South Sudan's secession.
They formed the "Sudanese Revolutionary Front", which says it fights to topple Bashir to secure a fairer share of government in a country dominated by three Arab tribes.
Fighters of the SPLM-North sided with southern Sudan during decades of civil war that ended with a peace deal in 2005, which paved the way for South Sudan's formal breakaway in July 2011.
Sudan on Wednesday started peace talks with the SPLM-North after a thaw in relations with South Sudan.
(Writing by Ulf Laessing; Editing by Mark Heinrich and Mike Collett-White)