Some Silver Brigade may recognise this beach. This is Changi Beach, a place where many of the Silver Brigade grew up with. Still popular but not the only beach attraction in the island. The good thing, it is free.
Look at the picture carefully. Look at how the steel plates folded, outwards and upwards. It looks like the explosion was from inside or from below. An internal accidental, hitting a mine below?
If it was hit by a torpedo, the steel plates would be folding outwards from one side. You make your conclusion.