“We are facing a global wave of terror… the attack in Burgas was led by members of Hezbollah and sponsored by Iran,” Barak told public radio.
“The Al-Qaeda and Islamic Jihad networks also operate globally,” he added, citing a long list of recent attacks or attempted attacks on Israelis around the world.
Bulgaria’s Interior Minister Tsvetan Tsvetanov said on Thursday that the attack on the airport at the Black Sea resort of Burgas was carried out by a suicide bomber, and left six Israelis and one Bulgarian dead.
Barak said Israel’s intelligence services were working with partners overseas to share information about potential attacks.
“There are often very big successes, but it doesn’t always work and we must continue to live. We will do everything possible to track down the perpetrators and instigators of the Burgas attack and punish them,” he added.
On Wednesday, Israeli Prime Minister Benjamin Netanyahu publicly accused Tehran and Lebanese Shiite group Hezbollah of involvement in the attack.
“All the signs point to Iran,” Netanyahu said in a statement, which said the blast was the latest in a string of attempts to attack Israelis in Thailand, India, Georgia, Kenya, Cyprus and other places.
And in a phone call with Bulgaria’s Prime Minister Boyko Borisov, Netanyahu “indicated that Iran and Hezbollah were conducting a global terror campaign against Israelis across the world,” a statement from his office said.
Speaking to public radio on Thursday, Foreign Minister Avigdor Lieberman also pointed the finger at Iran and Hezbollah.
“It’s Hezbollah helped by the Iranian Revolutionary Guard that is responsible for this suicide attack. This is proven information,” he said, indicating that Israel was facing a “global terrorist war financed and organised by Iran.”
Lieberman said the latest toll he was aware of was five Israelis killed and three wounded. He said a sixth person had been killed in addition to the suicide bomber.
Meanwhile, an Israeli army spokeswoman said a first plane bringing home some of the injured was to land in Israel at around 3:00 pm (1200 GMT).
“The whole aim is to bring back the injured for treatment in Israel,” she said.
It was expected to land at a military airport, she said, adding that it was not clear when the second plane would return.
Wednesday’s explosion, which ripped through a bus picking up tourists arriving from Tel Aviv, was the deadliest attack on Israelis abroad since 2004.