Fifteen people have been killed and 70 injured after a fire tore through one of Nairobi’s largest open-air markets in the early hours of Thursday.

The blaze started at around 2.30am local time (12.30am BST) and spread through Gikomba market, nearby flats and shacks before being contained about 90 minutes later, according to St John Ambulance.

Nairobi county commissioner Kangethe Thuku said six bodies had been recovered but nine were still inaccessible after the fire, which broke out in a timber yard.

“About five ... arrived dead in the hospital but we still have about nine bodies in the burning buildings because we want to confirm and ensure the safety of those buildings,” he said.

The cause of the fire has yet to be established, but “for now we have declared this site a crime scene”.

Rescue teams are searching for more bodies and survivors in Gikomba market, which is located in the Pumwani area of the capital city.

Many Kenyans shop for secondhand clothes from the market, which also supplies other vendors with used clothes from Europe and the United States.

Residents said the crowded market has had fires multiple times in recent years and traders have suffered huge losses.

One market trader, Ruth Kaveke, only managed to save a wad of burned currency from her cloth-making store. It is the second time her business has been destroyed by fire.

“I live in the market because it is convenient and I wanted to be close by; just in case of fire I could salvage my property,” she said.

The market is a five-minute walk from Nairobi’s central business district in an area targeted by the Nairobi County Government for an upgrade.

Thomas Mutie, the acting chief executive of Kenyatta National Hospital, said it is on alert for more victims. “In case we have any more, we are ready for them,” he said.