Aika Rey | Rappler | November 29, 2017

The National Bureau of Investigation (NBI) said there was no mechanical or electrical defect in the coupling device of the Metro Rail Transit Line 3 (MRT3) train coaches involved in the detachment incident earlier this month.

On Wednesday, November 29, MRT3 technicians led the dismantling of the coupling device as the NBI observed with a group of forensic experts.

"We saw in our initial findings that there is no defect insofar as the electrical and mechanical aspect of the coupler assembly is concerned," NBI Special Action Unit chief Joel Tovera said in a mix of English and Filipino.

Tovera added that they will probe deeper into the possibility of human intervention.

"But as I have said this is just the initial findings, we will also connect this to other aspects of our investigation like the statements of the persons of interest we've been investigating in the past week and more to come," said Tovera.

On November 16, commuters walked along the MRT3 tracks from the Ayala Station to the Buendia Station after a train coach got detached from the main train. Operations of the railway system were disrupted.

In a briefing, MRT3 technicians said train detachment due to mechanical or electrical fault is "impossible," pointing to human intervention as a possible cause.

Senator Grace Poe earlier called for the suspension of MRT3 operations but railway officials gave assurances that it is safe and that operating hours would be reduced to add more time for maintenance checks.

The MRT3 experienced 475 glitches from January 1 to November 17.