CAIRO, Egypt – Iraq’s former prime minister, Ayad Allawi, fled the holy shrine of Imam Ali in Najaf yesterday as crowds pelted him with vegetables, stones, and footwear – dealing a setback to his political campaign.

On the scene, CNN’s Nic Robertson said Mr. Allawi’s security detail fired shots during the escape and that he could smell burning rubber as the Iraqi politician’s motorcade of 15 cars left the scene. Shortly after the confrontation, Apache helicopters were dispatched to provide air cover to Mr. Allawi’s entourage, according to CNN.

The incident, captured on television news stations, could spell doom for Mr. Allawi’s bid to regain the prime minister post in Iraq on December 15, when Iraqis are scheduled to vote for party lists vying for control of the National Assembly. Mr. Allawi, whose largely Sunni Arab party controls 45 seats in the National Assembly, was expected to do well in this month’s elections as many Iraqis have lost faith in the current Shiite-dominated government.

But the footage of his escape from Najaf, aired prominently in Iraq and on the Arab world’s major satellite stations, likely will undermine his image as a tough leader willing to confront both the terrorists and the Shiite Arab security services he has pledged to discipline. The image of crowds throwing shoes and sandals at the former prime minister is particularly humiliating in Arab culture, where it is customary in the company of guests to avoid crossing one’s legs in a manner that even exposes the sole of one’s shoe.

Mr. Allawi said yesterday that he and his entourage cut their campaign stop short in Najaf after he spotted a member of the audience reaching for a pistol in what he said was an attempted assassination. “They were planning to kill the whole delegation, or at least me,” the Associated Press quoted Mr. Allawi as saying shortly after he arrived back in Baghdad. “One of them took out his pistol, but he panicked and it fell from his hand.”

The atmosphere leading up to the Iraqi elections has been particularly violent. Already one member of Mr. Allawi’s list has been gunned down. Yesterday, Iraq’s national security adviser said that authorities uncovered a plot by a Sunni Arab insurgent group to fire rockets at the court building where Saddam Hussein’s trial resumes this week.

A statement released by the office of the national security adviser, Mouwaffak al-Rubaie, said a group called the 1920 Revolution Brigades planned to attack the building during Monday’s court session. The statement said Iraqi intelligence uncovered the plot but gave no further details and did not say whether anyone had been arrested.

Mr. Allawi was named interim prime minister at the end of June 2004, after the coalition provisional authority, with the help of U.N. envoy Lakhdar Brahimi, selected a government in Baghdad to steer the country through the January 2005 elections. A secular Shiite, Mr. Allawi has kept close ties to former members of the Ba’ath party since the late 1970s, when he began working closely with British and American intelligence. But his connections to reformed Baathists have also cost him support among the majority Shiite population. One poster in Iraq features Mr. Allawi’s face superimposed on the body of Saddam Hussein. Reuters yesterday said that the former prime minister’s allies on the list have been told they cannot campaign in Najaf and nearby Karballah.

One of Mr. Allawi’s first acts as prime minister was to send Iraqi soldiers into Najaf to face down Moqtada al-Sadr’s rebelling militia. News reports speculated that yesterday’s incident in Najaf may have been drummed up by Mr. Sadr, the once outlaw cleric. Mr. Allawi told Reuters yesterday, “We believe this was premeditated.” The news agency quoted his aides as saying his assailants chanted support for backers of Mr. Sadr. Mr. Sadr had not as of last night offered a comment on the incident.

Mr. Sadr, along with other religious Shiite parties in Iraq, received a boost last month after aides to Grand Ayatollah Ali Sistani put out word for Shiite Arabs to vote for religious parties and not to split their votes with “marginal” non-religious ones. The edict could damage the prospects of Deputy Prime Minister Ahmad Chalabi, who split from the United Iraqi Alliance in October and announced his own largely secular list running under the banner of his old party in exile, the Iraqi National Congress.

Mr. Allawi last month was quoted in Arabic and English newspapers as saying that the security services in Iraq today are committing human rights atrocities in league with those of Saddam Hussein. The comments came after American soldiers raided a secret interior ministry prison in Baghdad and found evidence of torture among some of the prisoners, including one man whose skin was partially peeled off.