Smoke rises into the sky after an explosion at Burgas airport, outside the Black Sea city of Burgas, Bulgaria, some 250 miles east of the capital, Sofia, Wednesday, July 18, 2012. (Credit: AP Photo/ Burgasinfo)
(CBS/AP) BURGAS, Bulgaria - A lanky, long-haired man wearing a baseball cap and plaid shorts with a fake Michigan driver's license carried out a deadly suicide attack on a bus full of Israeli vacationers, Bulgarian officials said Thursday as authorities continued to analyze forensic evidence to determine the suspected bomber's identity.
Bulgarian television aired security camera footage Thursday showing the suspect wandering in and out of the terminal shortly before the blast. He was dressed as a tourist himself, wearing a baseball cap, T-shirt, plaid shorts and sneakers with short white socks. He carried a large backpack with wheels.
Interior Minister Tsvetan Tsvetanov said the bomber was believed to have been about 36 years old and had been in the country between four and seven days.
"We cannot exclude the possibility that he had logistical support on Bulgarian territory," the minister said. He declined to elaborate.
Officials were using DNA samples to try to establish his identity. Bulgarian Prime Minister Boiko Borisov told reporters that a Michigan driver's license was retrieved, but he said U.S. officials reported that "there was no such person in their database." Michigan is home to one of the largest Arab communities in the United States.
Israel stuck by its claim that the attack was carried out by Iranian-backed Hezbollah, a Lebanese Shiite Muslim guerrilla group, and threatened retaliation. Seven people -- five Israelis, the Bulgarian driver and the bomber -- died in the blast Wednesday.
Israeli Prime Minister Benjamin Netanyahu said Thursday that Iran and its protege Hezbollah have been carrying out a "global terror campaign" for more than a year that has targeted Israeli and others.
No group claimed responsibility for the attack. But Israel has attributed a series of attacks on its citizens around the world in recent months to Iran and its Shiite proxies, threatening to escalate a shadow war between the two arch-enemies.
The attack occurred shortly after the Israelis boarded a bus outside the airport in the Black Sea resort town of Burgas, a popular destination for Israeli tourists -- particularly for high school graduates before they are drafted into military service -- about 250 miles east of the capital, Sofia.
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The Israelis had just arrived on a charter flight from Tel Aviv carrying 154 people, including eight children. Some of them told Israeli television that they were just boarding the white bus in the airport parking lot for a ride to their hotel when the blast occurred.
Officials reported overnight that an eighth person had died, but later said that was incorrect.
Israel's military said a military plane carrying 33 Israelis injured in the bombing arrived Thursday in Israeli. At least two critically injured Israelis were sent to Sofia for treatment, according to the head of the Israeli military medical corps, Brig. Gen. Itzik Kreis.
A Bulgarian government plane will fly home 100 other Israelis who were not wounded but who want to cut short their vacation.
Bulgarian authorities Thursday dispatched 200 police to hotels where about 1,000 Israelis were staying just north of Burgas. A representative of the Ortanna tour company said about 10,000 Israelis had booked vacations in Bulgaria through the firm this summer and about half had canceled after the attack.
Israel blamed Iran and its Hezbollah proxies for the attack, saying they are waging a campaign against Israeli targets everywhere. Hezbollah used suicide attackers against Israeli troops during the occupation of Lebanon but does not have a history of suicide strikes abroad.
"All signs point to Iran," Israeli Prime Minister Benjamin Netanyahu said. "This is an Iranian terror attack that is spreading across the world. Israel will react forcefully to Iran's terror."
"The direct executors are Hezbollah," added Israeli Defense Minister Ehud Barak. "Israel will do all it can to find those responsible and punish them, both those who carried it out directly and those who dispatched them."
On Sunday, Cypriot authorities said they had arrested a 24-year-old man on suspicion of planning terror attacks. Cypriot radio said he was of Lebanese origin and carrying a Swedish passport. Netanyahu blamed Iran for the alleged plot.
On Thursday, Iran's state TV called Israel's claims that it was responsible for the Bulgarian attack "ridiculous" and "sensational."
But a former Iranian agent from that country's feared Revolutionary Guard corps - a man who's been on the inside - tells CBS News that a surrogate, stealth war, carried out in the shadows by both sides, has been going on for more than a year.
It began with the targeted killings of Iranian scientists working on that country's nuclear program.
Then a computer virus was covertly deployed against Iranian nuclear sites. The virus was designed to make the sites self-destruct. Iran publicly accused the U.S., Great Britain and Israel of being behind the plots.
Israel has not directly replied to the Iranian charges. But Israeli leaders have repeatedly said that "all options are on the table" in trying to disrupt Iran's nuclear program -- a phrase that is widely interpreted as meaning the possibility of a military strike and other measures that could include cyberwarfare.
Now, it appears to some that Iran is striking back.
"They're looking at this saying, 'We've got to respond. Aggression has been taken against us,"' says former CIA analyst Phil Mudd. "So that's the first factor. The second factor is, in the background, they're hearing the drumbeats of war."
In Berlin, German Foreign Minister Guido Westerwelle urged the Israelis to show restraint until "the real perpetrators and backers" are found.
In Washington, the Obama administration condemned the blast "in the strongest possible terms." White House press secretary Jay Carney said U.S. "commitment to Israel's security remains unshakeable."
Israel dispatched a military medical and relief team to Bulgaria, a European Union nation of 7.3 million that borders Greece and Turkey.
Bulgaria's government resisted Nazi demands to deport Jews to death camps in World War II. Many of them migrated to Israel when the Communists seized power after the war. Since the fall of Communism, Bulgaria and Israel have maintained friendly ties.
The Burgas airport was closed and traffic redirected. In Sofia, the capital, Mayor Yordanka Fandakova ordered a stronger police presence at all public places linked to the Jewish community. Some 5,000 Jews live in Bulgaria, most in Sofia.
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