Nine people have been arrested in Albania on suspicion of homicide and abuse of power following an earthquake last month that killed 51 people.
Prosecutors said 17 people, including builders, engineers and officials, were suspected of breaching building regulations that led to the collapse of buildings during the 6.4 magnitude quake on 26 November.
Eight of the suspects are still being sought by police.
Police chief of the port city of Durres, Lorenc Shehu, said preliminary investigations had established that irregularities had been the cause of building collapses that killed 23 people there.
Durres and Thumane, north of Tirana, were hit hard by the quake, which also left around 900 people injured and 5,000 homeless.
Among those arrested was an engineer who worked on one Durres building in which eight members of the same family died.
Illegal construction is rife in Albania, where chaotic development exploded after the fall of communism in 1990.
Many buildings lack proper permits and do not adhere to safety codes.
The earthquake was the deadliest in several decades in Albania, which lies near a tectonic fault line.