Rescue teams are searching for survivors after an eight-storey residential building collapsed in the Turkish city of Istanbul, killing at least three people. It was not immediately clear how many people were trapped in the wreckage or what caused the collapse of the 27-year-old apartment block in Kartal district, on the Asian side of the city, on Wednesday afternoon.

Istanbul Governor Ali Yerlikaya told reporters at the site that 43 people were registered in 14 apartments at the address, but that the top three floors of the building had been built illegally.

Rescue workers pulled at least 12 people, including a nine-year-old boy, out of the rubble and were working to free more who were trapped.

“Racing against time, the teams are working, making great sacrifices,” Binali Yildirim, a former Turkish prime minister and the current speaker of parliament who is running for mayor of Istanbul in March’s local elections, told reporters at the site.

He added that neighbouring buildings had been evacuated in case they had also been damaged.