A driver said the dispute arose because of a disparity in pay between Chinese and Malaysian bus drivers.
Three China bus drivers who are currently facing criminal charges for their alleged involvement in the strike last November have been sacked by SMRT for not turning up for work.
He Jun Ling, Gao Yue Qiang and Liu Xiang Ying did not report to work after they were released on bail on 6 December 2012, said an SMRT spokesman.
Over the course of the past six weeks, SMRT said it tried to maintain contact with them but they had, until recently, refused direct communication with SMRT even though they remained under employment and were still paid according to the terms of their employment.
They also moved out of the company-provided accommodation and rejected SMRT's offers of alternate accommodation to them.
A fourth driver, Wang Xianjie, who faces similar charges but his employment contract expired on Jan 14.
SMRT said that for the case He, Gao and Liu, their continued absence from work without official leave and without informing their employer breached their employment contracts.
They were suspended from their duties pending an internal disciplinary inquiry. All three failed to attend the inquiry which was held on 17 January 2013 and their contracts were subsequently terminated by the transport operator.
Last November, over 170 SMRT bus captains from China went on a full-day strike at their Woodlands dormitories to protest over low pay and poor living dorm conditions. About half continued the strike into a second day.
Four of them were subsequently "charged for engaging in a conspiracy" to "instigate workmen employed by SMRT Buses Ltd" to take part in a two-day strike.
A fifth driver was sentenced to six weeks' jail. 29 others were deported back to their homeland.
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