The U.S. Embassy in Asmara does not process Immigrant Visas. All Immigrant Visas for Eritreans are handled at the U.S. Embassy in Addis Ababa or Nairobi.
The fiancé(e) K-1 nonimmigrant visa is for the foreign-citizen fiancé(e) of a U.S. citizen. The K-1 visa permits the foreign-citizen fiancé(e) to travel to the United States and marry his or her U.S. citizen sponsor within 90 days of arrival. You can learn more about fiancé(e) visas on usvisas.state.gov.