An announced emergency evacuation from Sudan was thrown into confusion Saturday when the U.S. Embassy there said it was too dangerous to evacuate its citizens, just hours after the country’s military chief vowed to help relocate nationals of several countries, including the United States.

As fighting between two clashing military factions entered its second week, the army chief, Gen. Abdel Fattah Burhan, who is Sudan’s de facto leader, said in a statement Saturday that his troops would facilitate the evacuation of diplomats and citizens from Britain, China, France and the United States “in the coming hours.”

Soon after, however, the U.S. Embassy said in a security alert that “due to the uncertain security situation in Khartoum and closure of the airport, it is not currently safe to undertake a U.S. government-coordinated evacuation of private U.S. citizens.”

It was not immediately clear whether the United States planned an evacuation of embassy staff. Current air evacuation plans focus on getting diplomats and their families out first.

The contradictory statements were the latest signs of the chaos and confusion that have prevailed in Sudan, Africa’s third-largest nation, since fighting erupted April 15 between two factions whose leaders are vying for control over the country. At least 400 people have been killed in the ensuing clashes and 3,500 injured, according to the United Nations. They include at least 256 civilians who died and 1,454 who were wounded, according to a doctors trade union.

Countless residents of the capital, Khartoum, have fled the city, where bodies line the streets, to find refuge in safer suburbs and states. More than 15,000 people from the western region of Darfur have fled into neighboring Chad, and humanitarian organizations have reported being unable to work amid the incessant fighting.

With fighting persisting for an eighth day, it remained unclear how and when any departures could be organized. The international airport in Khartoum has been closed amid the fighting, and roads across the country remain dangerous.

On Friday, a team of experts inspected the Khartoum airport’s runways, according to a security official. The Sudanese military, which is fighting against the rival Rapid Support Forces paramilitary group, has increased its presence on the airport’s perimeter.

Several countries have positioned planes in neighboring countries, ready to fly when the airport is clear.

But any flights in and out of Khartoum are risky. The area around the airport, including the military headquarters, has been the site of some of the most intense fighting over the past week. And residents said that gunbattles continued to rage in several parts of the city Saturday morning, including near the airport.

With the flights most likely to be limited to diplomatic staff, at least initially, other groups are making plans to leave the city by road. The United Nations is preparing a large convoy to leave as early as Sunday, having negotiated safe passage with the warring parties. It was unclear whether non-U.N. personnel would be allowed to join the convoy.

Road travel also involves considerable risk. Khartoum is 600 miles from the border with Egypt and 525 miles from Port Sudan on the Red Sea — about the same distance from New York City to Columbus, Ohio, but through areas contested by the two sides.

Foreigners and wealthy Sudanese are turning to private security companies to help escape Khartoum, but risks remain. The security official said that one convoy carrying 17 people had made a 14-hour journey from the city Friday, only to arrive in a heavily contested area where gunbattles continued Saturday.

For many, the most immediate challenge is to safely leave the homes where they have been sheltering for the past week. One U.N. official said a diplomatic vehicle traveling to her home had been stopped by armed men and robbed of all valuables.

Some people have managed to leave, however.

Burhan said that diplomats from Saudi Arabia had been evacuated by land to Port Sudan, in the country’s east, and taken to Saudi Arabia, with a similar operation expected to take place for Jordanian citizens. Hungary’s foreign minister said Saturday that 14 Hungarian citizens and 48 foreign nationals, most of them American and Italian citizens, had been evacuated by sea and were headed to Egypt.

As the clashes continued, Sudan’s health care system was teetering, and there were few signs that the two warring factions would stop fighting. Out of 78 major hospitals in the country, 55 are operational, according to the physicians association.

“The health care system is about to collapse,” Mohamed Eisa, the secretary-general of the Sudanese American Physicians Association, a U.S.-based nonprofit, said in a telephone interview from Khartoum. “We must secure a safe passage for the injured.”

Gunfire had stopped Friday evening, leaving Khartoum residents hopeful that a break was in sight. Eisa said that for the first time, he had been able to get some sleep at his home in southern Khartoum, where the fighting has been continuous.

It did not last long.

He woke up Saturday morning to the sound of gunfire and heavy machinery. “It was as if nothing had happened,” he said of the dashed hopes for some respite.