Polio patient shot dead on bus in northwest Pakistan . Female suicide bomber attacks bus with police on it , source : BBC . Pakistani official says ` ` homegrown terrorists '' may be responsible . Officer dies in bombing of Pakistan founder 's home .
Polio workers shot dead on Sunday in northwest Pakistan . Female suicide bomber attacks bus with women on it , source tells CNN . Pakistani official thinks `` homegrown terrorists '' may be responsible . Officer dies in bombing of Pakistan founder 's home .