LHASA, Dec. 19 -- Dust is obscuring the sights of Lhasa, capital of southwest China's Tibet Autonomous Region on Thursday, disrupting flights.

Renowned as "sun city", Lhasa normally basks under blue skies with rarely a foggy day.

Liu Yijun, a senior engineer at the local meteorological observatory, said a sharp drop in temperature, lower pressure and accumulated particulates are main causes of the murk which is forecast to last for another two days.

The dust cloud first manifest itself in Lhasa and neighboring counties of Quxu and Gonggar early on Thursday morning.

Poor visibility at Gonggar Airport in Lhasa meant two flights were canceled and another seven were unable to land. The airport had resumed normal operation by 2 p.m..