Bulgaria Bus Bomber Had up to Five Foreign Helpers

The bomber who blew up an Israeli tourist bus in Bulgaria in July, killing six people, had up to five foreign helpers locally and the attack was planned abroad, the interior minister said Thursday.

"The number of people who participated on Bulgarian territory is between three and five," Tsvetan Tsvetanov told the 24 Hours newspaper.

"To date we have no proof that any of them was Bulgarian," Tsvetanov added. He said the attack at Burgas airport was plotted outside Bulgaria over a period of a year and a half.

The probe into the identity of the foreign bomber, who killed five Israeli tourists and their Bulgarian driver as well as himself in the July 18 attack, has collected "lots of evidence," the minister said.

"Still, the time has not yet come to voice any concrete accusation against the people or groups who performed this terrorist act (...) We must work with concrete evidence. We have to be very cautious as national security is concerned," he added.

The accomplice theory gained ground right from the start of the investigation but Bulgarian police have so far released only one computer-generated image of a suspected helper, in addition to a composite portrait of the presumed bomber himself.

Israel had immediately blamed Iran and its "terrorist proxy" Hizbullah for the bombing, which was the deadliest on Israelis abroad since 2004. Iran denied any involvement.

Bulgaria has so far refrained from pointing a finger at anyone.

Holiday resorts on Bulgaria's Black Sea coast are popular with Israeli tourists.