A massive fire erupted in a supermarket in the Russian city of St. Petersburg at 8.30 a.m. local time (GMT +3) on Saturday; all personnel and customers have been evacuated.

A major fire occurred in the Lenta supermarket in St. Petersburg on Saturday morning, having quickly swept through the entire building and spread to the roof, with the area covered by the blaze being about 5,000 square metres. More than 800 people, including staff and customers, have been evacuated.

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According to preliminary data, the cause of the fire may be an electrical malfunction, an emergency services representative told Sputnik.

"The preliminary cause of the fire is a malfunction of the electrical equipment under the roof of the shopping centre," the source said.

The source from the emergency services said that roof of the store had collapsed on an area of 3,800 sq. metres, but there were no reports of any casualties.

В Питере горит Лента. Пожар в гипермаркете на Набережной Обводного канала, 118 корпус 7 pic.twitter.com/n8wxLKrTMh — Искандер13 (@13iskander131) 10 November 2018

Another emergency services source told Sputnik that two helicopters had been alerted at Pulkovo Airport in St. Petersburg to extinguish the fire.

“Mi-8 and Ka-32 helicopters with spill-over devices with a capacity of 5 tonnes at Pulkovo airport are being alerted,” the source said.

🔥В Санкт-Петербурге горит крыша гипермаркета "Лента"

Площадь пожара составляет почти 5 тыс. кв. метров

Здание покинули 800 человек.

МЧС: "На Обводном канале происходит пожар на кровле гипермаркета "Лента", ранг пожара — номер три" pic.twitter.com/PbUxYrYqL6 — Марина Саакян 🇷🇺 (@marinochka_san) 10 November 2018