- Israel claims Iran is behind explosion on Bulgarian bus
- It also has blamed Tehran for attacks on diplomats
- Iran has pointed to Israel in scientist deaths
Wednesday's explosion on a bus carrying Israeli tourists in Bulgaria came on the 18th anniversary of the attack on a Jewish community center in the Argentinian capital of Buenos Aires, in which 85 people were killed.
Argentina's top prosecutor last year blamed Iran for the 1994 attack. Israel also holds Iran responsible for the attack.
Tehran has denied any connection to the Buenos Aires bombing, which it has condemned.
Such claims and counterclaims between Israel and Iran have been common in the past three decades, with each blaming the other for attacks on their citizens.
Israel, without citing evidence, quickly pointed to Iran in the Bulgarian incident.
"All signs point towards Iran," Israel Prime Minister Benjamin Netanyahu said. "Over the last few months we have seen Iran's attempts to attack Israelis in Thailand, India, Georgia, Kenya, Cyprus and other countries."
At least seven people were killed in the Bulgarian explosion.
Iran had no immediate reaction.
After Iranian nuclear scientists were assassinated in Tehran, Iran blamed Israel. When attackers targeted Israeli diplomats this year, Israel blamed Iran.
Iran hanged a man who was convicted of killing one of its nuclear scientists, state-run Press TV reported in May.
Majid Jamali Fashi was convicted of the January 2010 killing of Massoud Ali Mohammadi, an Iranian university professor and a nuclear scientist. He was also convicted of spying.
Prosecutors accused him of working for the Mossad, the Israeli spy agency, and said he was paid $120,000 by Israel to carry out the hit.
Israel typically does not comment on such claims.
In January, Iran sent a letter to the United Nations secretary-general alleging the killings of the scientists were terrorist attacks that followed a clear pattern. "There is firm evidence that certain foreign quarters are behind such assassinations," the letter said.
In April, Iran said it broke up an Israeli "terror and sabotage network" that was planning attacks within the country, making a number of arrests while confiscating weapons and equipment, state-run media reported.
"The complicated and months-long measures and moves made by the Iranian intelligence forces to identify the devils led to the discovery of the Zionists' regional command center ... and discovering the identity of the agents active in that command center," a statement from the Iranian Intelligence Ministry said.
A spokesman for the Israeli Foreign Ministry said then that every few months Iran spreads disinformation and there was no basis to the story.
Ties between Iran and Israel unraveled after the 1979 Islamic revolution in Iran.
After he was elected in 2005, Iranian President Mahmoud Ahmadinejad began spouting anti-Israeli and anti-Western rhetoric.
Yet it has been Iran's nuclear program that has raised the prospects of armed conflict.
Iran has been in a protracted dispute with the United States and other countries over its nuclear program, which it claims is for peaceful purposes.
But many Western countries fear the program is a cover for Iran to develop nuclear weapons.
Just this week, U.S. Secretary of State Hillary Clinton said Iran has not made a "strategic decision" to address concerns.
Israel, which is believed to have its own nuclear arsenal and is alarmed over Tehran's hostility toward the Jewish state, has said it may attack Iran to try to stop the country from developing nuclear weapons.
"There is a world agreement that the Iranian government is after nuclear weapons and that its policy of terrorism is endangering everybody. There is a global understating that we must do everything we can to prevent Iran from endangering others," Israeli President Shimon Peres said, according to the Israeli Foreign Minister's office.