sentences:  On 13 April, the Islamic State of Iraq posted a message on an Islamist website claiming to have sent ""A knight from the state of Islam... [into] the heart of the Green Zone"" to carry out the attack.It is not clear whether this claim is genuine, though some who monitor such websites believe it is.In February 2009, two bodyguards of Iraqi National Dialogue Front MP Mohammed al-Dayni were arrested on suspicion of the attacks.