Iraqi insurgents have struck a major blow to efforts to draft the country’s landmark constitution. Three Sunni Arabs on the team responsible for writing the charter have been assassinated, prompting four other members to suspend their work. The killing has being seen as an attempt to intimidate Sunnis into withdrawing from the body and thus delay or scupper the constitution, which has been touted as a big chance for peace. In other violence on Wednesday, a bomber strapped with explosives blew himself up among a group of Iraqi army recruits in Baghdad, killing six people and wounding around 25. A three-day onslaught of attacks at the weekend thought to have been ordered by the Jordanian terrorist Abu Musab al-Zarqawi claimed around 150 lives.