Four people died when two apartment buildings collapsed in the Italian city of Palermo from causes not yet determined.

Firefighters in the Sicilian capital said Tuesday that the collapse occurred around 11:30 p.m. Monday as the buildings were being evacuated, following a call from a neighbor who warned residents about strange noises coming from one of them.

The tallest building of the two, whose walls had begun to crack some time ago after an additional, prefabricated story was built on top of it, was the first to come crashing down and contributed to the collapse of the other.

Besides the dead, about 10 people were slightly injured.

"We rushed to the scene after a call notified us of problems with the structure of one of the buildings. When we got there, we found a terrifying situation and ordered the two buildings evacuated, saving the life of a disabled person among others," the chief of the Palermo firefighters, Gaetano Vallefuoco, said.

"Some of the residents managed to get out of the buildings, but all of a sudden the buildings crashed down. Some people remaining inside were able to escape anyway, but four others were not so lucky," he said. EFE