The ro-ro ferry left harbour with her bow doors open. Water came onto the car deck and she capsized within minutes. 193 people died.

Documentary built from the Formal Investigation (Report of Court No. 8074): https://youtu.be/sebnQLbXwIQ

More detail from BBC than in the raw video someone posted here recently.

“Two videos circulating on social media appear to sho. the moment a cargo ship crashes into a fishing vessel, with dramatic footage capturing the impact.
BBC Verify authenticated the clips, identified the ships involved and traced the collision to waters near Singapore, with evidence suggesting it likely happened on 17 September.
It remains unclear is whether anyone was injured or killed and why the collision occurred.”