This just happened.

I was making a call outside the office building. This is a relatively well-guarded area but open to the public. Police are always in sight.

A middle-aged guy is following a young lady who has a piece of jewelry dangling on her backpack. She was on a call.

Just in front of me, on step away, this guy started to sneakily steal the jewelry (which is fake, the lady told me later).

I yelled at him right away: NO! NO! You cannot do that!...STOP!!!

Then he stopped (I was about to push him away) and said:
What's your problem? Ah?

Cannot believe this is happening in daylight, at the center of LA.