As with any tragedy, in the aftermath of the Sydney Hostage Crisis people are mourning - and most of them don't know the victims.
In these three still images we see body language examples of hand coverings of the mouth, mouth-nose, and mouth-nose-eyes to varying degrees
The causes of these nonverbal behaviors is not from any type embarrassment of public display of emotions - rather it is a natural and common (though not ubiquitous) reaction during moments of a dissociation between what is known by the intellect and what is being felt by the emotional brain. The mind is trying to process the emotions and catch up with what the rational brain already understands.
Of course these are three still images and not a comprehensive assessment of any of these scenes or the people in them. However those who display these nonverbal signals upon seeing, thinking of, hearing about, etc. another person's/peoples' suffering - indicate higher empathy and sincerity quotients vs. those who do not exhibit such body language. There are of course many nonverbal signs of sincerity and empathy.
My condolences to the family and loved-ones of Ms. Katrina Dawson and Mr. Tori Johnson.
See also:
Nonverbal Communication Analysis No. 3039: Selfies and Smiling at the Sydney Hostage Crisis
Nonverbal Communication Analysis No. 3038: Johnny Manziel's first NFL Start - a Representative Body Language Moment
Nonverbal Communication Analysis No. 3037: Angelina has Chickenpox and will not be able to attend some events for the opening of her movie, "Unbroken" - Body Language Tells
Nonverbal Communication Analysis No. 3036: Angelina Jolie runs into Amy Pascal after email Hack
Nonverbal Communication Analysis No. 2322: Jeb Bush & Matt Lauer - Which one is the Narcissist? Body Language Red Flags
Nonverbal Communication Analysis No. 2982: Politicians Should Never Do This If They Want To Be Elected - Hillary Clinton's Body Language Faux Pas
Nonverbal Communication Analysis No. 2313: Elisa Lam Video in Elevator at Cecil Hotel - What Her Body Language Tells Us
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