Khartoum, June 1 : Sudan's Civil Aviation Authority has extended the closure of the country's airspace to June 15 amid continued armed conflict between the Sudanese Army and the paramilitary Rapid Support Forces. In a notice to airmen, or NOTAM, on Wednesday, the authority decided to extend the closure of airspace for all civil flights, with the exception of those carrying humanitarian aid. The authority said that the closure could be extended again in the future, Xinhua news agency reported. Since the outbreak of the deadly armed clashes in the Sudanese capital Khartoum and other areas on April 15, the country's airspace has been closed as air navigation systems at Khartoum International Airport have been affected. More than 800 people have been killed, and nearly 1.4 million people have been forced to leave their homes since the conflict began, with more than one million people internally displaced and about 3,45,000 people crossing into neighbouring countries for safety, said the United Nations Office for the Coordination of Humanitarian Affairs in its latest report on Sunday. /IANS