A five-story apartment building collapsed in Istanbul early Wednesday, killing at least two people and injuring 26 others, authorities said.
A city worker who chanced to walk by shortly after midnight saw the building swaying and alerted people inside by shouting and throwing stones at the windows, said Istanbul Mayor Kadir Topbas.
Some people managed to safely flee, but the dead and injured had become trapped on a stairway as the building toppled, said Ali Karahan, chief of Istanbul firefighter department.
It was not clear how many people were inside when it came down. Istanbul Gov. Muammer Guler said at least 27 people were living there and several people were in a coffee house in the basement.
Rescue teams with sniffer dogs worked under floodlights to find out whether there were any others trapped under the rubble.
"We think maybe just a few more people remain buried if anyone left," Guler said.
There was no immediate official word on what caused the collapse in residential Zeytinburnu district. Topbas said that the building was listed as among those that needed to be demolished because their ability to withstand a strong earthquake was questionable.
Such collapses in Turkey are sometimes associated with earthquakes, a constant worry for residents of this sprawling city of more than 12 million.
Geologists have urged the Turkish government to tear down some 50,000 buildings that would probably collapse if a big quake hits Istanbul.
They say hundreds of thousands of other buildings that rise in an unstable mass of brick, mortar and stone, need to be reinforced.
Topbas said the collapsed building was on the list of 16,000 other buildings marked as unsafe and needed to be pulled down in Zeytinburnu district alone.