Mr Yerlikaya also said the textile workshop on the ground floor of the building was operating without a license.
"Three people were killed and 12 others were wounded", the governor's office said in a brief statement, noting that three of the injured were in "critical condition".
Speaking to reporters at the site, Soylu said rescue work has been ongoing for 31 hours in an effort to reach more survivors.
Overnight, emergency services rescued a nine-year old boy from the debris of the building that collapsed on Wednesday afternoon.
At least three people have been found dead in the rubble while 13 others were pulled out with injuries.
The incident occurred Wednesday in the Maltepe district of the Turkish city.
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Islamic State leader Abu Bakr al-Baghdadi declared the group's "caliphate" in 2014 in territory stretching across Iraq and Syria. The U.S. military presence in Syria has offered the Kurds a measure of protection against any Turkish offensive.
Some residents have been trapped inside the wreckage, but officials haven not provided the exact number of people under the rubble.
Neighbour Cemile Dag said the collapse had brought to mind haunting images from a deadly natural disaster that hit northwestern Turkey in 1999, destroying thousands of homes.
Authorities evacuated seven surrounding buildings, and one was under serious risk of collapse. I looked behind me and the building, like a deck of cards, fell to the ground. "There were wails, screaming".
The incident was a stark reminder of the fragility of parts of Istanbul's residential infrastructure, with several buildings collapsing in recent years.
"Racing against time, the teams are working, making great sacrifices", said Yildirim, the current parliament speaker who is running for mayor of Istanbul in Turkey's March 31 local elections.
Officials have said the building's top three floors were built illegally, although the cause of the collapse is still under investigation.