SMRT trains
SMRT train travels along a track in a neighbourhood in Singapore. Reuters

At least 23 people were injured when Singapore's mass-rapid rail system suffered a collision when a train operated by SMRT Corp hit another stationary one on Wednesday.

Two SMRT employees and 23 passengers sustained light to moderate injuries and were sent to two hospitals, SMRT and Singapore's Land Transport Authority said in a statement.

They are investigating the incident, which took place around Joo Koon station in the western part of the city-state at 08:20 am local time.

Wednesday's collision was the latest knock on Singapore's reputation for slick infrastructure after the city-state witnessed a commuter chaos earlier this year.

In August, two of Singapore's five mass transit rail lines suffered signaling failures, leaving thousands of disgruntled passengers late for work.

The latest incidents showcase the growing infrastructure burden that many Asian cities are facing as they upgrade transit systems to cope with swelling urban populations.

Since 2000, the island nation's population has jumped from less than 4 million to more than 5.6 million, straining a public transport network that has struggled to keep up.