Turkish authorities have widened investigations in relation to buildings that collapsed in the catastrophic earthquakes earlier this month, which flattened swathes of the country’s southeastern region.

Investigations have been launched against around 612 people, and 184 suspects accused of responsibility for the toppled buildings have been taken into custody pending trial, Justice Minister Bekir Bozdağ said Saturday.

The magnitude 7.7 and 7.6 quakes struck on Feb. 6 in southeastern Turkey, also severely hitting neighboring Syria, and destroying around 164,000 buildings, containing some 520,000 apartments, in what is described as the worst disaster in Turkey’s modern history.

Overnight, the death toll from the earthquakes rose to 44,128 in Turkey. That took the overall number of deaths in Turkey and Syria to more than 50,000.

Those in custody as part of the investigation include construction contractors and building owners or managers, Bozdağ said in televised comments from a coordination center in the southeastern province of Diyarbakır, one of the 10 provinces hit by the disaster.

“The detection of evidence in the buildings continues as a basis for criminal investigations,” the minister added.