SINGAPORE, � The collision involving two Mass Rapid Transit (MRT) trains at Joo Koon station was the second such incident in MRT's 30-year history, Channel NewsAsia reported yesterday.

The report said the first incident occurred on Aug 5, 1993, six years after the MRT system began operations in 1987.

It involved a front-to-back collision between two trains at Clementi station, and resulted in 156 injured commuters.

Some of them were flung against panels and steel railings inside the train or piled on top of one another.

The collision was due to an east-bound train from Jurong stopping at Clementi MRT station for two minutes longer than scheduled due to a technical fault.

The report said operations at the three affected stations, Clementi, Buona Vista and Commonwealth, resumed within a day after intensive checks were carried out by engineers from SMRT, then known as Mass Rapid Transit Corp (MRTC).

An independent inquiry panel was formed to probe the incident.

On Oct 19, the inquiry panel said the accident was caused by a 50 litre oil spill from a maintenance locomotive, which had been carrying out maintenance work about 5am, on the day of the accident.

The inquiry panel also said the accident could have been prevented, had the staff understood the gravity of the situation and dealt with the oil spill sufficiently aggressively or promptly.

Following the findings, MRTC revised its operating procedures to require station masters to inspect the platform tracks for oil and implement safety measures in the event of an oil spill.

In addition, the train operator announced plans to purchase new locomotives to replace the existing ones for track maintenance as the new locomotives were not prone to the same type of hydraulic leakage.

Today's collision saw 28 passengers, including two SMRT staff sustaining light to moderate injuries.

The MRT system forms the major component of the railway system in Singapore, with the network covering 198.6km of route and having 119 stations.

The eight lines were built by the Land Transport Authority, a statutory board of the Government of Singapore, and the trains are operated by SMRT Corporation and SBS Transit.