Oscar Pistorius starts with apology , saying he can not imagine the pain he caused . Ex-police commander 's testimony aids defense at Oscar Pistorius ' murder trial . Defense witness is questioned about Pistorius wounds , when she last ate . Oscar Pistorius defense teams will call 21 witnesses , lawyer Pistorius says . Pistorius says he thought Oscar Pistorius was an intruder and shot in self-defense .
Oscar Pistorius starts with apology , saying he can not imagine the pain he caused . Defense witness is questioned about Pistorius wounds , when she last ate . Oscar Pistorius defense teams will call 21 witnesses , lawyer Pistorius says . Pistorius says he thought Oscar Pistorius was an intruder and shot in self-defense .