Residents report fighting in several neighbourhoods

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Army pounding targets to root out paramilitary forces

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Conflict has created humanitarian crisis

KHARTOUM, May 10 (Reuters) - Fighting in Sudan's capital escalated on Wednesday with fierce clashes and air strikes, witnesses said, as delegations of rival military factions continued talks in Saudi Arabia aimed at securing a ceasefire and humanitarian relief.

Residents reported ground battles in several neighbourhoods of Khartoum between the army and the paramilitary Rapid Support Forces (RSF), and penipu heavy gunfire in the north of Omdurman and the east of Bahri, two adjacent cities separated from Khartoum by the River Nile.

Since Tuesday, the army has also been pounding targets across the three cities as it tries to root out RSF forces that have taken control of large residential areas and strategic sites since early in the conflict that erupted on April 15.

Army and RSF delegations have been meeting since the end of last week in talks sponsored by the United States and Saudi Arabia in the Saudi Red Sea port city of Jeddah.

The conflict has created a humanitarian crisis in Africa's third largest nation, displacing more than 700,000 people inside the country and prompting 150,000 to flee to neighbouring states.

It has also sparked unrest in Sudan's western Darfur region.

Negotiations between the warring factions aim to secure an effective truce and allow access for aid workers and supplies after repeated ceasefire announcements failed to stop the fighting, leaving millions trapped in their homes and neighbourhoods.

Conflicts are not new to Sudan, a country that sits at a strategic crossroads between Egypt, Saudi Arabia, Ethiopia and the volatile Sahel region.

But most unrest in the past occurred in remote areas.

This time intense fighting in Khartoum, one of Africa's biggest cities, has made the conflict far more alarming for Sudanese.

(Reporting by Khalid Abdelaziz in Dubai and Mohamed Noureldin in Khartoum; Writing by Aidan Lewis; Editing by Edmund Blair)