Five people, including two young brothers, were killed in an apartment fire in a working class district of the western German city of Cologne early on Saturday, police said according to Reuters. Police said four of the victims, including brothers aged five and seven, and their father, were from Congo. The boys' mother waved to firefighters from a balcony for help. She and her two-year-old son were taken to hospital with injuries. The authorities said they could not say whether the victims were from the Democratic Republic of Congo or Congo Republic. Police said the fire began on the second floor of the nine-storey building shortly before 2 a.m. (0100 GMT) and spread to the fourth floor where most of the victims were found. They said they believed it was not an arson attack, but they were still trying to determine the cause. An elderly German couple lived in the second-floor apartment where the blaze began. Aged about 70, both were taken to hospital with severe injuries. The man later died. Nine other people were taken to hospital with injuries.