Video: https://nypost.com/2024/03/26/us-news/baltimores-key-bridge-collapses-after-being-struck-by-a-container-ship/

Play it and watch carefully and looks for white explosions:

1. top side of the structure in the center of the bridge - you can see it after is starts going down,

2. top side of the structure on the left,

3. the main bar that was hit by the vessel - the part below the road level, on the same height as the top side of the vessel

In 1 and 2 you can see white smoke going down following the place where the explosion was.

Number 1 is where the “key stone” would usually be on the arch.

Number 2 is where the left part breaks later.

Number 3 is where and when the main pillar starts to fall.

EDIT: On this video below you can watch the left part zoomed out - there are 2 explosions there and the smoke is easier to notice: https://greatawakening.win/p/17siNus3gG/moment-of-collision-and-collapse/c/