VOICED : Ucrania en alerta ante avance rebelde

The pro-Russian insurrection is spreading in Eastern Ukraine, with rebels taking control of strategic buildings in several cities, inspired by Crimea's example. There is a push for a referendum to decide on federalism. Pro-Russian militants have taken hostages, including international observers. In response, the Kiev government has put its military on high alert, preparing for a potential Russian invasion. Interim President Oleksandr Turchinov acknowledges difficulties in regaining control, as some military personnel are cooperating with separatists.

¿Qué tipo de referéndum se menciona en el texto y cuál es su propósito?

¿Qué admitió el presidente interino Oleksandr Turchinov sobre el control militar en algunas regiones?