SINGAPORE - The hairline cracks found on the 26 China-made trains did not pose a safety concern, hence the issue was not made public when the defects were first discovered in 2013, said Transport Minister Khaw Boon Wan on Tuesday (July 12).

The defects, which required the trains to be sent back progressively to the manufacturer in Qingdao to have their car-bodies replaced, also did not impact reliability or capacity, Mr Khaw said during a press briefing.

This issue - which was first brought to light by Hong Kong media FactWire last week - is a "seemingly routine matter" that had been "mis-spun" by "mischievous hands", said Mr Khaw.

The trains are manufactured by Chinese-Japanese consortium, Kawasaki-Sifang, and are used on the North South-East West Line (NSEWL).

Tests found that despite the hairline cracks, the bolsters could still withstand loads of three times greater than its normal use, and this is an acceptable safety margin, said the LTA.

Under the rectification works, the bolsters used will be cast in Japan rather than from China.