Nigerian authorities say they are working to evacuate some of the 5,000 Nigerians stranded in Sudan amid fighting there.

The National Emergency Management Agency, or NEMA, on Monday said authorities have concluded plans to begin evacuating the first group of 3,500 Nigerian students in Sudan, beginning Tuesday morning.

The director of special duties at NEMA, Onimode Bandele, told VOA via phone that the plan is for students to be taken by bus to Cairo and then flown to Nigeria.

Bandele did not say when the remaining nationals will be evacuated.

"This is a country that is in turmoil. You don't just go in there [and] want to bring people out, for security reasons," Bandele said. "In an attempt to evacuate, we should be mindful of the fact that we do not want to lose any life to it. But now that there's a window, the government is exploring that window to get these people back to safety."

Nigeria's Foreign Ministry says Sudan's government has yet to give final approval for the evacuations.

A power tussle between Sudan's military and strong paramilitary group, the Rapid Support Forces, led to fighting on April 15 in the capital of Khartoum.

Officials say more than 400 people have been killed and thousands more wounded.

Many Sudanese and foreigners are fleeing the fighting, but millions of others have taken refuge in their homes and schools.

Nigerian student Abdulaziz Jikanliman, who is stuck in a school hostel, says he and those around him live in perpetual fear.

"You can hear the gunshots around, little bombings around. We're all scared. Nobody wants war. People are really starving. Many have no money to drink water, talk less of food to eat," he said.

Nigerian authorities on Sunday said it would be too dangerous to evacuate citizens without security clearances.

But union groups such as the Nigerian Labor Congress and the National Association of Nigerian Students, NANS, have criticized authorities for not acting sooner.

"They have taken too long," said Babatunde Akinteye, vice president of NANS. "If not for our cry, the way we started talking about it, our government might not even do anything. Now they say they want to start evacuation tomorrow. As we speak to you, there's no official statement to the student community on where to meet, how to prepare."

Both factions have ignored cease-fires in the past, including a three-day halt last Friday to mark the Eid al-Fitr holiday, which ends the Muslim holy month of Ramadan.