Those were people planning to bring down a big building that would have seen 3-4 skycrappers down.
I would send someone down to them to talk to them first and then give them a warning. Don't just shoot carte blanche. It will inflame the situation. They should police officers at the location not snipers on roof's. Kenyan police are totally useless. THey need a new training program that teaches them how to tell with this new urban young people in kenya.
In a normal situation, yes, but in a charged situation where criminals are planning a big thing, I think shooting them point blank is the best strategy. They are terrorists! I have not seen one incident where Police provoke protesters; it is always someone trying to loot or do something stupid. Remember, Police, by large, are just like regular Kenyans; they are quickly bound to do something silly, like looting someone's business.