Two four-story buildings adjacent to each other in the Moroccan city of Fez collapsed overnight, and 22 people are dead, in the second time this year that buildings in the city have collapsed.

Morocco’s state news agency, MAP, said that the two buildings were home to eight families. Sixteen people were injured and brought to the hospital. Authorities said the neighborhood was evacuated, and search and rescue efforts were ongoing.

It was unclear what brought about the collapse or how many people were not accounted for. An investigation had been opened, authorities said. MAP reported that the structures were constructed in 2006 during an initiative called “City Without Slums.“

Fez is the third largest city in Morocco, and hosts the Africa Cup of Nations this month, besides hosting the 2030 World Cup in football. It is most well kept for its walled city, crammed with medieval souks. It’s also one of the impoverished urban centres in the country, with aging infrastructure being common.

Such building collapses are not rare in Moroccan cities with a rapid increase in population. A collapse in May in Fez killed 10 people and injured seven in a building that had been scheduled to be evacuated, Moroccan outlet Le360 added.

Building codes are often not enforced in Morocco, especially in ancient cities, where old homes with many apartments made from cinderblock are common. Though the buildings that collapsed on Wednesday had been constructed in accordance with code, the Hespress news outlet reported, additional floors had been added to the structure.

Infrastructure inequality was an issue in protests sweeping the country earlier this year, as demonstrators decried the government’s focus on investing in new stadiums rather than addressing inequality in health care, education, and other public services.