A Saudi leader of Al-Qaeda in the Arabian Peninsula has urged sympathisers in the Saudi security forces to kill Christians living in the kingdom,in an audio message released on Wednesday. The purported audiotape,posted on a website used by Islamists,also repeated an often-made call to overthrow the Saudi government. "Those of you who work in guarding the tyrants of princes or ministers,or the compounds inhabited by Christians,or can reach them,should seek God's help and kill them," said AQAP's number two,Said al-Shihri. Shihri,a former inmate of the US military detention centre in Guantanamo Bay,Cuba,claimed that AQAP has received correspondence from members of Saudi armed forces asking for "guidance."