Responsibility for the shooting on Fontanska Road

I read the news that a shooting occurred on Fontanska Road in Odesa, resulting in a man's death, and the police are still establishing all circumstances and the person involved. If, for example, someone witnessed such an event or even was nearby and saw or heard nothing, can they be held responsible for not rendering assistance or for not reporting it to the police? I am very interested in what responsibility witnesses might have in similar cases.