Moscow, Apr 3 (IANS/RIA Novosti): At least 17 people died in a fire that swept through a market warehouse in Moscow early Tuesday, Russia's emergencies ministry said.

The fire began around 4.50 a.m. in a warehouse at the Kachalovsky market.

Police said the fire may have been caused by a heater that had been left on as temperatures dropped to around zero degrees Celsius overnight.

Rescue workers were continuing their work at the scene hours after the blaze.

The fire broke out shortly after a blaze at a tower at an under-construction skyscraper that will be Europe's tallest upon completion.

"We believe they were migrant workers who lived at the market," a ministry spokesperson said. "We are now trying to determine which republic they came from."

"The bodies are being identified, but this is difficult as they are all badly burnt," a Moscow migration service spokesperson said.

"I only saw burnt bodies, hands and legs," said a woman at the scene looking for friends. "It wasn't clear who was burnt."

She also said the victims all lived and worked at the market.

"The death toll will certainly rise," an official said.

Monday evening's fire in the Federation Tower complex was visible across large areas of Moscow.

Russia has an appalling fire safety record. Some 12,000 people died in fires across the country in 2011, according to emergencies ministry figures.