KARACHI, May 19: At least two persons were killed and four others injured when a weather system carrying dust storm hit the city on Saturday evening.

A woman and a teenaged boy were electrocuted in different city areas, while tin roofs of houses and other facilities fell in the city due to the dust storm.

Officials at the Pakistan Meteorological Department said that the weather system entered from Iran and after passing through Balochistan struck the city in the evening.

They said that the minimum visibility was at 50 metres, but Karachi airport authorities claimed that the visibility had dropped to zero for a brief period, owing to which one flight was affected for a few minutes.

A met official said that the dust storm enveloped the city at around 7.15pm. During its peak, the wind speed touched the mark of 35 to 36 knots (almost 70 kilometres per hour) and lowered the visibility to around 50 metres. This severe condition remained for around half an hour, he added.

However, he said, the situation started to improve shortly and by 8pm the wind speed had dropped to around 10 knots (20 kilometres per hour) and the visibility had also improved and was measured at more than four kilometres.

He said though the severe part of the weather system had passed, a few patches were still to come, but these hopefully would not be as severe.

He said the system, which was picked up by the met department radars/equipment at around 3pm, would pass on completely during the night.

He said the system was travelling eastwards and, after passing through the eastern parts of Sindh, would enter western India.

He said the wind speed and the dust content in the wind was more severe in the Nooriabad area, than in Karachi. He said a warning had been issued to the airport authorities at around 4pm informing them of the ensuing weather system.

The Civil Aviation Authority said that the visibility at one point had dropped to zero owing to which an aircraft of a Saudi Arabian airlines, which had taxied and come almost to the runway to take-off, was told to wait for a few minutes and after a wait of about five minutes it was allowed to fly off following a slight improvement in visibility. They said that since no flight was scheduled to land during that time, the schedule was not disturbed.

They said that at around 8.15pm visibility had recorded at six kilometres.

A similar type of low visibility weather had gripped the Karachi airport a few days back owing to which many flights scheduled to land here were diverted and only two flights had landed here, during which tyres of one of the aircraft had burst.

Meanwhile, rescue workers said that an unidentified woman was found electrocuted in Gulshan-i-Hadeed.

They said 17-year-old Ahmed Khan was also electrocuted near Boulton Market. He originally hailed from Chaman and was a wage earner.

Officials at the central fire station said four persons were injured in at least two tin roof collapse incidents due to dust storm in different parts of the city.