A Reuters video from the scene of the attacks in St Petersburg and nearby on Friday showed two giant plumes of thick smoke rising into the sky.
Tatyana Kim, founder of "Moscow's answer to Amazon" and Russia's wealthiest woman, said the latest attacks had targeted warehouses in St Petersburg, in the surrounding Leningrad region and in Simferopol, the main city in Russian-controlled Crimea.
"We managed to save some of the premises and goods. I would like to thank our staff, our heroes - a swift evacuation was carried out at all warehouses," Kim said in a statement.
"According to preliminary reports, there were no casualties."
"All of our efforts are now focused on redistributing goods across our warehouses to ensure more efficient stock turnover and the economic stability of our partners," she said.
Wildberries, whose banking arm had sanctions imposed on it by the European Union this week over its financial contribution to the Russian budget, plays a central role in Russia's consumer economy.
Its targeting by Ukraine appears to be part of Kyiv's attempts to ensure ordinary Russians feel the impact of the war, which has raged on Ukrainian territory for more than four years.
The strikes, the fourth on Wildberries' facilities since last weekend, threaten serious losses for businesses that sell through Wildberries and potential disruption to customers who use it to buy clothing, appliances, medicines, cosmetics and a host of other products.
Ukrainian President Volodymyr Zelenskiy has described the targets as logistics hubs involved in supplying Russian forces with drone components and other equipment.
The Kremlin has denied that Wildberries handles military supplies. Kim has accused Ukraine of attacking ordinary people doing their jobs.
Eight Wildberries warehouses, accounting for over 10 per cent of the company's logistics capacity, have now been attacked since July 18 when the first attack on the retailer killed eight workers.
Kim said the company was working around the clock to try to maintain the quality of its service.
Two orders placed on Wildberries since the weekend by Reuters reporters were either fully or almost fully fulfilled on time.
Two other orders were still being processed. In normal times, Wildberries can handle over 20 million orders a day.
Together with smaller rivals, Wildberries and top competitor Ozon sell goods and services worth the equivalent of 8.5 per cent of Russia's gross domestic product and employ four million people, or more than five per cent of the country's workforce.
Russia has itself targeted Ukraine's logistics hubs as well as its energy system and power grid.
6°C