A police truck, a costa and a private truck were involved in the accident.
The road to Luzira has been blocked, causing heavy traffic to the city center.
The roundabout is an access route for travellers from Eastern Uganda and several residents of Kampala and Wakiso.
In a related development, a truck failed to make a turn along Entebbe Road, blocking other vehicles from accessing Kampala city.
Some people have been forced to walk, while those who can afford are using Boda bodas.
Transport fares have more than doubled.