Much of Aleppo was destroyed during the Syrian conflict that began nearly 12 years ago and left many of the remaining buildings in a dilapidated state.
“The number of victims of the residential building collapse… has risen to 16 deaths,” the state news agency SANA said.
Only one person has been rescued alive from the rubble of the five-story building that housed seven families, the Syrian interior ministry said.
It was not immediately clear whether anyone else had survived the tragedy in the city, Syria’s pre-war commercial center.
Earlier on Sunday, SANA gave an initial death toll of 10, which increased throughout the day as searches continued.
A Kurdish news agency reports that five children are among the dead.
The casualties included Syrians displaced during the country’s years of fighting, a war monitor said.
Local residents told AFP that about 35 people lived in the building.
Video footage shared on state television showed dozens of rescue workers at the site, with some using their bare hands to dig into the gray rubble. Earth-moving machines scooped up the pieces of building material, creating dust in the air.
SANA quoted a police source as saying earlier that the building, in Aleppo’s Sheikh Maksoud neighborhood, had collapsed “due to a water leak” in the foundation.
The district is mainly inhabited by Syrian Kurds under the authority of the People’s Protection Units (YPG) militia, which is part of the de facto army of the Kurds.
However, Aleppo itself is under government control, which has recaptured it from rebels in devastating urban fighting.
The British based Syrian Observatory for Human Rights reported that the victims included displaced people from Afrin, further north, where neighboring Turkey launched an offensive in 2018.
Nearly half a million people have died in the Syrian conflict that began in 2011 and displaced about half of the country’s pre-war population.
Many of those forced from their homes had to move to buildings that were structurally unsound, resulting in relatively frequent collapses.
Last September, a building collapse in the Ferdaws district of Aleppo killed 10 people, including three children.
In February 2019, a war-damaged apartment building in the city also collapsed, killing 11 people, including four children.