A police spokeswoman says six construction workers have been killed in the Ugandan capital when a basement they were building collapsed on them.

Police spokeswoman Judith Nabakooba says at least 10 other workers are trapped under the debris of the basement that collapsed midday Tuesday. The workers were building the basement of an office block.

Nabakooba says five others have been seriously injured and rushed to a local hospital.

She says the police and other security agencies are trying "to save those still buried."

Survivor James Mwase says he was shocked to find most of his colleagues buried under the debris.