The Seoul Metro plans to provide nearly 400 toilets from this month in drivers' cabs and increase the number of staff bathrooms at stations, a spokesman said on Thursday.

'A major concern is the smell,' said Mr Kim Kyung Mo.

The incident that prompted the move took place in December when a driver apparently suffering from diarrhoea leaned out of his compartment and fell on the tracks. He was hit by another train, local media reported.

The toilets consist of a collapsible seat that stands a few centimetres off the ground and a receptacle. The device can be stored in a compartment about the size of a thick briefcase.

'Seoul Metro believes this step will help our staff better focus on transporting our citizens safely,' it said in a news release.

REUTERS