Heavy fog in New Delhi [Images] and surrounding areas disrupted the schedules of several flights in the capital on Sunday. Some flights were cancelled and several delayed due to almost zero visibility, caused by foggy conditions.

A similar situation had been witnessed last year, when dense fog had disrupted flight schedules and caused chaos in Delhi, Srinagar [Images] and Chandigarh airports. The government had then assured that the situation will not be repeated in 2008.

Union Minister for Civil Aviation Praful Patel is currently not in Delhi. "The minister is not in Delhi and you will have to wait for answers to your questions till he returns," a senior official in the Ministry for Civil Aviation told rediff.com.

Delhi airport authorities claimed that technology, in which flights could land or take off in spite of zero visibility, had already been installed at the Indira Gandhi [Images] International Airport. "They have been put into place, but the same systems have to be installed in the aircraft and the pilots have to be trained to use them," she said

Airline companies refused to reveal the number of flights which had been diverted or delayed due to the dense fog. Temperatures are expected to fall further in the capital on Monday, due to heavy snow in Shimla and Kashmir.