They were trapped when a 38m-long span became dislodged from its piers.The fallen span is made up of 14 segmented box girders and weighs 650t.

Syarikat Muhibar Perniagaan dan Pembinaan is contractor for the work package where the accident happened.

MRT Corp chief executive officer Datuk Wira Azhar Abdul Hamid said that the corporation and the project delivery partner MMC Gamuda KVMRT (PDP) have begun investigations to determine the cause of the accident.

"Initial investigations have revealed that the work method approved for the installation of parapets were not adhered to," he said. " We will investigate why this happened, and no stone will be left unturned so that we can get to the bottom of this tragic incident. We will also not spare anyone whose actions are found to have caused or contributed to this accident."