Three people are trapped under concrete blocks weighing 300 tonnes in an incident at the MRT construction site near Kota Damansara.

According to the Selangor Fire and Rescue Department, first responders arrived at at the scene at about 10pm after receiving a distress call 15 minutes prior.

In a statement MRT Corp said that the three workers feared dead are Bangladeshi nationals Mohamad Faruk Khan, Mohammad Elahi Hossain and Mohammad Alauddin Molik.

Rescue efforts are currently on-going.

"A span of the guideway has dislodged from its piers and fallen on the ground below.

"The span, which was made up of 14 units of segmented box girders was 38m in length and weighed 300 tonnes," MRT Corp said.

It said that the construction area, where the Kwasa Damansara station will be located, is not accessible to the public.

MRT Corp has also suspended all work where the incident happened.

The subcontractor for the package is Syarikah Muhibbah Perniagaan dan Pembinaan Sdn Bhd.

“Although investigations are underway, MRT Corp assumes full responsibility for the incident.

"Once investigations are completed, action on those responsible will be taken,” MRT Corp chief executive officer Azhar Abdul Hamid said form the scene of the incident.

Last June, MRT Corp terminated a subcontractor when a metal slab fell onto a passing car at the Pusat Damansara station construction site.

The car sustained extensive damage, but the driver escaped unhurt.