A Durban municipal building was evacuated on Saturday after a fire ripped through it, police said.

Inspector Michael Read said the fire started on the fourth floor of the Martin West building on Smith Street around 10am.

"The people inside were evacuated and fire officials are at the scene putting the blaze out," Read said around 2pm.

No injuries had been reported and the cause of the blaze was not known. The Martin West building consists of offices where people pay their water and electricity accounts.