Kenyan officials say a six-story residential building in a low income area of the capital has collapsed under heavy rain and flooding.

They said it isn't immediately clear whether there are injuries or fatalities. Kenya Red Cross says they have sent a search-and-rescue team to the Huruma area.

Japheth Koome, Nairobi's police chief, said hours-long traffic jams caused by flooded roads Thursday have prevented rescue teams from reaching the scene. Kenya is in the midst of its April-May rainy season.

Because of a high demand for housing in Nairobi, some property developers bypass building regulations to cut costs and maximize profits. The Architectural Society of Kenya has estimated that 50 percent of structures in Nairobi are not up to code.