Iraqi Death Hints of Iran's Role in Syrian Crisis The fighter's body was collected at an Iraqi border crossing with Iran, then carried on Monday through the streets of this southern city as mourners hailed his sacrifice in protecting a revered shrine in Syria. Diaa Mutashar al-Issawi was one of several Shiite fighters from Iraq who have trickled into Syria for months, providing a measure of support for Syrian regime forces battling mainly Sunni rebels. They are drawn by a sense of religious duty to ensure the sanctity of the revered Sayida Zeinab shrine outside the Syrian capital of Damascus as sectarian divisions harden in Syria's 2-year-old civil war. Al-Issawi is not the first Iraqi Shiite fighter thought to have died in Syria. But Iran's alleged role in repatriating his body strengthens suggestions that Tehran is involved in coordinating the movement of foreign fighters to aid its embattled ally, Syria. Iran is a key backer of Syrian President Bashar Assad's regime, and the United States suspects Tehran is using Iraqi airspace to shuttle weapons to Syria. Iraq remains officially neutral in the Syrian conflict, and officials had no comment on the return of al-Issawi's body. But the Shiite-led government in Baghdad fears Assad's ouster would lead to the rise of a conservative Sunni government in Syria. That could fuel renewed Sunni-Shiite strife in Iraq, where sectarian violence is on the rise. Assad's Alawite sect is a branch of Shiite Islam. "It was a religious and ethical duty to go to Syria and defend our holy shrines," said an Iraqi Shiite fighter from Basra who referred to himself only by the nickname Abu Zeinab, fearing reprisals. "Martyr Diaa and I fought together ... to foil the Takfiris' attacks," he said, using the term for a radical ideology that urges Sunni Muslims to kill anyone they consider an infidel. Journalists in the southern oil hub of Basra saw al-Issawi's coffin - similar to the those Iran once used to repatriate the dead during the Iran-Iraq War - leaving atop a vehicle from the Iraqi side of the Shalamcha border crossing with Iran. Masked men at the scene insisted photographers not take pictures as a convoy of around 20 cars departed. Iranian officials could not be reached for comment. At a funeral procession later in the morning, police blocked roads as dozens of tribesmen and Shiite clerics carried the coffin through the streets. Some in the crowd vowed to make a similar sacrifice and chanted slogans against the Sunni-dominated Free Syrian Army rebel group and the al-Qaida-affiliated Jabhat al-Nusra, which in the past year has become the most effective fighting force within the opposition trying to topple Assad. Iraqi Shiites who make the journey to Syria say their aim is to defend the Zeinab shrine, which marks what is believed to be the grave of the granddaughter of the Prophet Muhammad. A placard held aloft among the mourners called al-Issawi a "happy martyr" who died in the grounds of the holy site. Syria has several sites revered by Shiites, and the war has sparked fears that Sunni extremists, many of whom consider such shrines heretical, could attack them. The 2006 bombing of a shrine in Iraq came close to plunging the country into civil war. Al-Issawi was killed in a mortar attack during the past two days, according to Ali Falih Madhi, a prominent member of the Hezbollah Brigades in Basra who is widely known by his nom de guerre Abu Mujahid al-Maliki.