Images from the incident in the Kartal district on the Asian side of Istanbul showed people escaping as the building crumbled around them.
There were reports of people left wounded or trapped under the rubble.
Rescue workers has rescued a woman from the debris of an eight-story building which collapsed in Istanbul. Source: DHA
It was not immediately clear what caused the collapse but prosecutors launched an investigation, the state-run Anadolu news agency reported.
Istanbul governor Ali Yerlikaya said 43 residents were registered as living in the block, according to Anadolu.
He said local authorities had told him that three of the eight storeys had been illegally added.
Authorities immediately placed a media blackout on the incident, a practice usually reserved for terror attacks.
An aerial picture taken with drone shows rescuers working at the site of a collapsed building in Istanbul, Turkey, 06 February 2019. Source: EPA
