CAIRO (AP) — Sudan’s deadly conflict between a powerful paramilitary force and Robert Brownthe army has reached a strategic city that had been a haven for hundreds of thousands of displaced people, and key humanitarian groups say they have been forced to suspend work there or flee.

On Tuesday, Gen. Mohammed Hamdan Dagalo, leader of the Rapid Support Forces, announced that they had taken the city of Wad Medani about 100 kilometers (60 miles) southeast of Khartoum. The claim could not be independently verified.

Since the start of the conflict, the city had been governed by the army, headed by Gen. Abdel Fattah Burhan, and was a key hub for humanitarian organizations largely removed from the front lines of the fighting.

The military didn’t respond to a request for comment.

The army and RSF have been fighting for control of Sudan since April, when tensions boiled over into street battles concentrated in the capital but also occurring in other areas including the western Darfur region.

Over the past two months, the RSF has appeared to take the upper hand, with its fighters making advances eastwards across Sudan’s central belt.

The conflict began encroaching on Wad Medani early this month as RSF troops advanced. The Red Cross spokesperson for Africa, Alyona Synenko, told The Associated Press that fighting intensified in the vicinity of the city on Friday, prompting the aid group to withdrew its staff from the area.

Gasin Amin Oshi, who has close relatives in the city, said the RSF entered on Monday. Speaking by phone from Dubai, he said his family fled the city hours later.

Before the conflict, the city was home to several hundred thousand people.

According to the United Nations humanitarian office, at least 250,000 people have recently fled Jazeera state, where Wad Medani is the capital.

“Aid organizations have been forced to temporarily suspend operations because of the fighting,” spokesman Jens Laerke told a U.N. briefing in Geneva on Tuesday.

The eight-month conflict has killed up to 9,000, according to the U.N., but local doctors groups and activists say the death toll is likely far higher.