The body of a Chaldean Catholic archbishop was found in a shallow grave in northern Iraq, two weeks after he was kidnapped by gunmen in one of the most dramatic attacks against the country's small Christian community. The sad discovery of Archbishop Paulos Faraj Rahho's body came on a day that saw more violence elsewhere in Iraq. A parked car bomb exploded Thursday in a commercial district of central Baghdad, killing 18 people and wounding dozens more, police said. Gunmen also killed five members of an anti-al-Qaida group near Tikrit, and a correspondent for a newspaper in Baghdad. Pope Benedict XVI, US President George W. Bush and Iraq's prime minister all deplored the archbishop's death, with the pontiff calling it an "inhuman act of violence that offends the dignity of the human being and harms the peaceful coexistence of the dear Iraqi people." Since the US-led invasion in 2003, Iraqi Christians have been targeted by Islamic extremists who label them "crusaders" loyal to US troops. Militants have attacked churches, priests and businesses owned by Christians. Many Christians have fled the country, a trend mirrored in many dwindling pockets of Christianity across the Islamic world. Rahho, 65, was seized on Feb. 29, just minutes after he delivered a mass in Mosul, a city considered by the US military the last urban stronghold of al-Qaida in Iraq. Three of Rahho's companions were killed.