An apartment building in Egypt's Mediterranean port city of Alexandria collapsed early Wednesday killing at least 12 people, a police official said.

At least six other residents were wounded when the six-story building collapsed in the early hours of the morning while most of its residents were still sleeping.

The official added that rescue workers are searching for survivors and police have launched an investigation into the cause of the collapse.

The official spoke on condition of anonymity because he was not authorized to talk to the media.

Shoddy materials, illegal construction and corruption are usually blamed for frequent building collapses in Egypt.