Buddhist monks are not supposed to be Zombies.
Buddha was a fighter in his own way.
He faced Angulimaala and won.
A monk should be aware of surroundings
and should response positively.
If a monk acts with aversion, or greed
or as a zombie
he is worse than an animal.
Kung Fu and Karate were created by Buddhist monks.
It is their response to their offenders.
Mahinda may be trying to make a situation like in Burma.
I am happy that other monks behave more wisely than Burmese monks.
When we don't act against a sinner personally,
whole nature takes responsibility
and punishes him accordingly.
The sheer depression which Mahinda going through now is the result.