Fighting in Sudan rages on for the seventh day. The U.S. is preparing troops to enter the African nation to possibly help evacuate U.S. Embassy staff from the country.

There are an estimated 19,000 American citizens in Sudan, in addition to U.S. Embassy staff, so getting all of them out will likely prove to be a challenge. Heavy shelling has hit the capital’s international airport hard, making it basically inoperable, and the airspace over Sudan is currently closed, The New York Times reported.

Because of the current state of fighting and shelling, Vedant Patel, a U.S. State Department spokesperson, said, “it is currently not safe to undertake a U.S. government-coordinated evacuation of U.S. citizens,” per the Times.

At least 330 people have been killed and 3,200 have sustained injuries from the violence. The World Health Organization said those estimates are probably an “underestimation of the true impact of the crisis,” Ahmed Al-Mandhari, WHO regional director for the Eastern Mediterranean, said during a press conference, per ABC News.

What started the fighting in Sudan?

The fighting stems from two warring generals fighting for control of the country. As plans were being prepared to turn control back to civilian rule, tensions began to rise between the two factions as to who would have the most power.

Gen. Abdel-Fattah Burhan is over the nation’s armed forces who are clashing with Gen. Mohammed Hamdan Dalago, who is in charge of the Rapid Support Forces military group.

After two failed cease-fire attempts, fighting has continued nonstop in the country’s capital of Khartoum since Saturday.

How will U.S. troops get U.S. embassy staffers out of Sudan?

U.S. troops are planning on possibly being stationed at nearby Djibouti, “to provide the administration an option to launch an evacuation operation,” Deputy Secretary of State Wendy Sherman told lawmakers Wednesday, per Politico.

Some lawmakers have expressed concerns about staff members and Americans still inside the country. But Sen. Tim Kaine, D-Va., said the U.S. government is “very much on top of it.”

“Arrangements have been made. They’re sheltering in place and currently all secure, all accounted for and in communication with them,” Kaine told Politico. “There’s a whole-of-government effort to figure out exactly how to make sure that they continue in safety.”