SINGAPORE - Yishun MRT station was packed with commuters on Friday morning as a track fault delayed train services for about one and a half hours on the North-South line.

Train service resumed at around 9.25am.

Train operator SMRT first alerted commuters that there was an additional 15 minutes travelling time between Choa Chu Kang and Admiralty stations at around 8am.

This was revised at 8:49am to an estimated 25 minutes of additional travelling time.

A free bus service from Yew Tee to Toa Payoh was stopped after trains began running normally.

Financial consultant Andy Heng, 26, said he waited for 15 minutes before he could board a train at Sembawang. The train that he was on stalled four times along the way and he alighted at Ang Mo Kio station to take a taxi instead as it was traveling "too slowly". He was at least half an hour late for work.

"Breakdowns are unavoidable sometimes but they have been happening so often despite frequent maintenance so I think it's time the operators try something different and do a overhaul," he said.