JERUSALEM (Reuters) -- Israeli Defense Minister Ehud Barak said on Thursday that the Iranian-backed Lebanese group Hezbollah carried out the deadly bomb attack on a bus carrying Israeli tourists in Bulgaria on Wednesday.

Bulgarian officials said six people were killed when the bomb went off outside Bulgaria's Burgas airport. Israeli media reported that eight people had been killed and that six of them were Israelis.

"The immediate executors are Hezbollah people, who of course have constant Iranian sponsorship," Barak told Israel Radio.

The tourists had arrived on a charter flight from Israel and were on the bus in the airport car park when the blast tore through the double-Decker. Body parts were strewn across the ground and mangled metal hung from the bus's ripped roof.

"We have established a person who was a suicide bomber in this attack. This person had a fake driving license from the United States," Interior Minister Tsvetanov told reporters at the airport of Burgas, a city on Bulgaria's Black Sea coast.

Tsvetanov said special forces had managed to obtain DNA samples from the fingers of the bomber and were now checking databases in an attempt to identify him.

He said Bulgarian security services had received no indications of a pending terrorist attack in the Balkan country.

Video surveillance in front of the airport and the investigation showed the bomber could not be distinguished among arriving Israeli tourists. "He looked like everybody else - a normal person with Bermuda shorts and a backpack," he said.

The interior ministry said the eight dead included the Bulgarian driver of the bus and the bomber.

About 30 lightly injured Israeli tourists will be flown back to Israel in the coming hours, Tsvetanov said.

Hours after the attack Israeli Prime Minister Benjamin Netanyahu said Teheran was behind the attack and that "Israel will react powerfully against Iranian terror." There was no immediate Iranian reaction to the Israeli accusation.

The blast came on the 18th anniversary of a 1994 bomb attack on the headquarters of Argentina's main Jewish organization by a Hezbollah suicide bomber, which killed 85 people.

Israeli officials had previously said that Bulgaria, a popular holiday destination for Israeli tourists, was vulnerable to attack by Islamist militants who could infiltrate via Turkey.

Israeli diplomats have been targeted in several countries in recent months by bombers who Israel said struck on behalf of Iran.

Although Tehran has denied involvement, some analysts believe it is trying to avenge the assassinations of several scientists from its nuclear program, which the Iranians have blamed on Israel and its Western allies.

Israel and Western powers fear that Iran is working towards a nuclear bomb, but Tehran says its research is strictly for peaceful ends.

Both Israel and the United States have not ruled out military action against Iranian nuclear facilities.

Hezbollah is a powerful political party and militant group in Lebanon and fought a war with Israel in 2006. The group claimed victory even though Lebanon suffered high casualties.