At least six people were killed and five others injured on Friday when a four-storey building collapsed in Egypt's northern coastal city of Alexandria, official news agency MENA reported.

The five injured people, including two children, were transferred to the nearest hospital, and are in unstable conditions, it added.

The government had warned about possible danger of the building but the residents inside refused to leave, according to the report.

Public prosecutors have ordered an immediate investigation of the incident.