The train crashed into the side of the bus as it crossed the railway line during the peak hours of morning rush hour, local police commander Benjamin Nyamae said.[break]
"The number of dead is 12," said Nyamae.
An AFP photographer at the scene said the bus was buckled around the front of the train engine.
"The bus crossed the line as the train came at a high speed... several others are in hospital," said Nairobi police chief Benson Kibui.
The accident, in Nairobi´s Eastlands district, took place as the roads were crowded with passengers rushing to get to work.
Several injured have been taken to hospital, some in a critical condition, Kenya Red Cross said.
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