Backing the parent comment, please see https://www.pbs.org/newshour/world/report-says-200-environme...
Ironic considering that the original claim was:
>Many climate scientists sounding the alarm get attacked and silenced (and activists get killed!)
But the source you provide only mentions "environmental and land defense activists".
I vaguely recall a climate scientist disappearing under odd circumstances but I can't recall where. Maybe this was a scientist and activist in Latin America.
Still, climate activists are routinely targeted: https://www.bbc.com/news/science-environment-63064471
I'm still vaguely recalling an article about a climate scientist disappearing under suspicious circumstances, but I cannot find it now.