KUALA LUMPUR, June 11 — An issue with the rail signalling system along the Sungai Buloh-Kajang MRT line during the evening rush hour will be rectified as soon as possible, said RapidKL today.

RapidKL, through its Twitter and Facebook handle, had announced the train service delay between Batu 11 and Kajang was caused by intermittent signalling communication not responding properly at 4.29pm.

About 45 minutes later, RapidKL issued another follow-up announcement, stating affected train services will be back to normal within half an hour.

"Signalling issue from Batu 11-Kajang rectified. Our trains are now moving on manual mode. Train service for the entire line is gaining momentum and resuming to normal in approximately 30 minutes,” the update read at 5.14pm.

However, many Malaysians took to social media to rant about delay and being stranded at several train stations along the affected line as announcements on the delay were not clearly communicated to commuters.

A handler named @JHao97 on Twitter said, "I waited for an hour at the station but the train still not moving.”

Another handler, @MOHDRAFIZ said, "@MyRapidKL @MRTMalaysia Utter disaster. No clear instruction to either disembark or stay in the train at Tmn Suntex. Then the train moves again — when more than half of the passengers had alighted.”