Four blasts in the Iranian city of Ahvaz and two more in the capital killed at least nine people and wounded more than 70 Sunday, just five days before the nation's presidential election.
The rare outbreak of violence caught the country by surprise, and Iranian officials alleged that bombers had come from Iraq to disrupt Friday's balloting. Voters will be deciding who will succeed President Mohammad Khatami and guide the nation through a series of challenges.
In recent months, Iran has come under renewed international pressure over its nuclear program. And with U.S. forces fighting insurgents in neighboring Iraq, it fears that instability could seep across its border. Iranian officials are concerned that low election turnout could undermine the Islamic establishment at home and weaken its position in negotiations over its atomic program.
The front-runner in the election is Hashemi Rafsanjani, a veteran of the 1979 Islamic Revolution who served as president before Khatami and is regarded as a wily pragmatist, somewhat willing to engage with the West on specific issues. He is running against several more hard-line candidates, as well as reformist hopefuls who wish to see greater personal and political freedoms in the Shiite Muslim theocracy.
Sunday's deadliest bombs were aimed at government buildings in Ahvaz, the capital of oil-rich Khuzestan province in the southwest of the country. The city is on a desert plain just 80 miles from Basra, Iraq, across the Shatt al Arab waterway.
Ahvaz has been the scene of civil unrest in the last two months over a report that the government in Tehran wanted to change the ethnic makeup of the city by relocating Arabs living there in favor of ethnic Persians, the dominant group in Iran. Officials have denied any such plan.
According to Iranian sources in Basra, slogans have appeared on walls in Ahvaz stating that "the freedom of Arabs is restricted by Rafsanjani" and "anyone who participates in the elections will be killed."
Officials fear that unrest from Iraq may be spilling into Iran, in several possible forms, including supporters of former Iraqi leader Saddam Hussein; Sunni Muslim extremists; or members of the Mujahedin Khalq organization, an Iranian opposition group based in Paris and Iraq that has claimed responsibility for attacks against Iran's Islamic government in the past.
The governor of Khuzestan province, Fathollah Moin, told reporters that seven people had been "martyred" in Ahvaz and more than 70 injured. Most of those hurt were women and children, he said.
When asked whether anyone had accepted responsibility, Moin said there were various assumptions but no conclusions. He added that such acts weren't unprecedented in Khuzestan.
Unrest erupted in the province in April when a letter, purportedly written by former Vice President Mohammed Ali Abtahi, circulated insulting the large Sunni Arab population of southern Iran. Authorities said the letter was a forgery.
Moin said whoever carried out the bombings was "hand in hand with the enemy" and he hoped "the identity of those hated perpetrators would soon be known."
"Today in the run-up to the presidential election, most foreign media try unanimously to keep people from going to the polls," Moin said. "The events of today in Ahvaz had the same suicidal goal." He said, however, that the people of the city were loyal to the Islamic Republic and would take part with enthusiasm.
"Most certainly this time, too, the people will give a definite answer to the enemies of Islam and the revolution," he said. Voters will "show that they are strong defenders of the Islamic Republic in this region."
Some state radio stations in Iran ignored the explosions, whereas others reported them in detail.
State television reported that of the four bombs that exploded in Ahvaz, one was planted in a small Korean-made car, another in the bathroom of an office building and a third in a satchel. No detail was given on the fourth.
The bombs were reported to have exploded outside the governor's office, a state housing office, and near the home of the head of the province's television and radio stations.
There was some disagreement among radio and TV stations about the number of victims in Ahvaz, with most reports saying seven but one television channel saying eight. In Tehran, two people reportedly died.
At one of the blast sites in the capital, near Imam Hussein Square in the Martyrs neighborhood of eastern Tehran, a witness saw the bomb go off in a garbage bin near a gas station. A reporter saw the bin and a streetlight destroyed and a newspaper stand nearby slightly damaged.
A man who said he had been at a phone booth nearby said he heard an unbearably loud noise and felt the ground quake.
A police officer at the scene, Mehdi Omidi, said he saw that two people had severed limbs, one losing a leg and the other an arm. A 12-year-old boy said one man, who was bleeding heavily, died. The Islamic Republic News Agency said two people were killed, including a 60-year-old man.
Both Iranian and foreign reporters were able to look around the scene and speak to witnesses only briefly.
Security officers stopped many journalists and asked them to show identity and accreditation papers. After a few minutes, journalists were taken by Intelligence Ministry officials to a nearby building, where they were held for about one hour before being released.
Leaving the area after their detention, the journalists saw roadblocks being set up by members of pro-government militias, known here as the Basijis. They were stopping cars and looking into trunks.
Although Moin, the governor of Khuzestan, did not blame any one organization for the violence, other officials named several groups as the culprits.
The spokesman for Iran's Supreme National Security Council attributed the blasts to groups linked to Iraq's former Baathist government. In the 1980s, Iran fought an eight-year war against that Sunni-dominated regime, but Tehran has enjoyed increasingly warm relations with Baghdad since a Shiite-led government assumed power this spring.
At least one state radio program said the Mujahedin Khalq organization was responsible.
Mujahedin Khalq is on the U.S. State Department's list of terrorist organizations, but its political wing has been met with sympathy from some members of Congress who see it as legitimate opposition to religious rule in Iran. In Iran's official media, the group is a frequent target of scorn and is commonly referred to as the "Monafeqin," or "hypocrites."
An Iranian military source said that two months ago in Ahvaz, 16 people were killed in clashes between military forces and Arabs.
The same source said that local officials believed that the attackers who planted the explosives were Sunni Arab extremists who had slipped over the border from Iraq to undermine the election.
"The goal of such terrorist attacks is to exploit the situation in the southern districts of Iran because of its mixture of Arabs and Persians," said the source, who spoke on condition of anonymity. "They want to sow sedition and influence the electoral process which will take place in a few days.
"I think that Iran will witness similar attacks" before the election, he said, "attempts to intimidate people [and] to foil the election in Iran."
Special correspondent Siamdoust reported from Tehran and Times staff writer Daniszewski from London. Times staff writer Louise Roug in Basra contributed to this report.