SMRT has sacked eight staff and disciplined three others after 13 people were found responsible in a probe into the falsification of maintenance records sparked by a tunnel flooding incident last month.
Two executives held accountable by the investigation had resigned shortly after the incident, but the rail operator said it reserves the right to pursue legal action against them.
The MRT tunnel flooding incident left a section of the North-South Line inoperable for 20 hours.
A week after the disruptions, SMRT said the maintenance team that had failed to properly maintain a flood prevention system at Bishan MRT station would have their bonuses cut. Investigators have not found out why the pumps and related switches failed, although they concluded that the crew tasked with maintaining the system had not done so for nearly a year.