The report said the collision occurred around 6am along the Woodlands Crossing and involved two lorries, a bus and a car.
A check on the social media engagement site, stomp.straitstimes.com, showed that in pictures shared by netizens, all vehicles carried Malaysian-registered plate numbers.
Quoting the Singapore Civil Defence Force, the ST report said 26 people were injured and taken to hospital.
Meanwhile, the Immigration & Checkpoints Authority (ICA) posted an update on Facebook around 10am, saying that an affected lane had reopened at the Woodlands Crossing.
Two hours earlier, ICA reported a partial lane closure at the Woodlands Crossing due to a traffic accident.
According to the ST report, the Singapore Civil Defence Force was alerted to the accident at 6.10am.
Of the 26 injured, 13 were sent to the Khoo Teck Puat Hospital, 10 to the Tan Tock Seng Hospital and three to the Ng Teng Fong General Hospital, it said.
The report said that there were no life-threatening injuries and most of those taken to hospital suffered minor injuries.