Israeli diplomats in India and Georgia have been targeted in near-simultaneous strikes that Prime Minister Benjamin Netanyahu blamed on arch-enemies Iran and Hezbollah.
The bombing of an Israeli diplomat's car in New Delhi by an attacker on a motorcycle wounded four people, and an attempted car bombing in Georgia was thwarted.
"Today we witnessed two attempts of terrorism against innocent civilians," Mr Netanyahu said. "Iran is behind these attacks and it is the largest terror exporter in the world."
There was no claim of responsibility for the attacks. But Mr Netanyahu also said Israel had thwarted similar attacks in recent months in Azerbaijan and Thailand.
"In all those cases, the elements behind these attacks were Iran and its protege, Hezbollah," he said, vowing to "act with a strong hand against international terror."
Both Hezbollah and Iran have deep grievances against the Jewish state.
Hezbollah battled Israel in a month-long war in 2006, and on Sunday, the Lebanese guerrilla group marked the anniversary of the 2008 assassination of one of its commanders, Imad Mughniyeh, in a bombing widely believed to have been carried out by Israel. Iran suspects Israeli involvement in a series of killings of officials and scientists involved in its nuclear programme.
The New Delhi attack took place just a few hundred yards from the prime minister's residence as the diplomat's wife was heading to school to pick up her children.
When the car approached a crossing, she noticed a motorcyclist ride up and stick something on it that appeared to be a magnetic device.
The car drove a short distance, there was a loud sound and then an explosion and the car caught fire.
The woman, Tal Yeshova, was stable and conscious in hospital. Her driver and two people in a nearby car sustained minor injuries.
Israeli diplomats in India have been on constant alert since Pakistan-based militants rampaged across the Indian city of Mumbai in 2008, attacking luxury hotels, the main train station and killing six people in the Chabad Jewish community centre.
Authorities in the former Soviet republic of Georgia said a bomb was planted on the car of a driver for the Israeli Embassy.
He noticed a package underneath his car and called police who found and defused a grenade.
There was no immediate comment from Iran or Hezbollah. But speculation will undoubtedly be raised over the possibility of Iranian-linked payback for assassinations on nuclear scientists and other covert plots that Tehran has blamed on Israel's spy agency Mossad and Western allies.