This is another despicable act. Unfortunately being a christian in Pakistan is synonymous with being a sweeper and these extremists don't consider/treat them as human-beings. This is nothing but khulli badmaashi and must be condemned.
On a separate note I have yet to come across a mullah or maulvi who made a d'ua for all of mankind and not just muslims during the traditional Friday or Eid prayers. They always only pray for Islam and Muslims.** I asked one mullah about this ((after all isn't the rest of mankind (however mis-guided they are from our perspective...) His creation too)) **and not surprisngly he had no answer. Such narrow-minded thinking is drummed into us from a very young age and it's no surprise then that some of us grow up with very extreme/intolerant views about 'others'. Why can't they say a prayer, something like, "Oh Allah we are all so grateful to you that you gave us Islam......have your mercy on all human-beings and give guidance to us and the non-muslims amongst us."
What you wrote is Islam. But whom you asked, they may consider themselves Muslims but certainly they are not following Islam. If you will try to find out, you will learn that Prophet (SAW) regularly use to pray for mankind, not just Muslims. A person to be Muslim, he/she should have love and care for every creation of Allah (be they Muslims or non-Muslims) and should only hate wrong deeds (be those wrong deeds done by Muslims or non-Muslims). In this world there is nothing personal for a Muslim and thus a Muslim should give justice to even his worst enemy and no person should feel threatened by a Muslim.
If there would be group of Muslims then they would spread Islam (Peace and tranquillity) and other than trouble makers (Muttafanni) everyone would find refuge from them. If you ever see a group of people from whom people of different beliefs, casts, views, communities or religion feel threatened (in whatever way) then be assured that these people are not Muslims but soldiers of Shaitan and Jahannumi.