Israel has accused Iran and its ally Hezbollah, Lebanon's Shia movement, of being behind a bombing targeting embassy staff in India that injured four people, and the attempted bombing of an embassy vehicle in Georgia.
Tehran denied involvement in Monday's attacks and accused Israel of carrying out the attacks itself. Hezbollah made no comment.
In the Indian capital New Delhi, a bomb wrecked a car taking an Israeli embassy official to pick up her children from school, police said. The woman needed surgery to remove shrapnel but her life was not in danger.
Her driver and two passers-by suffered lesser injuries.
Israeli officials said an attempt to bomb an embassy car in the Georgian capital Tbilisi failed and the device was defused.
Israel had put its foreign missions on high alert ahead of the fourth anniversary this past Sunday of the assassination in Syria of the military mastermind of Hezbollah, Imad Moughniyeh. That attack was widely assumed to be the work of Israeli agents.
Binyamin Netanyahu, Israel's prime minister, blamed Iran for the attacks on its embassy staff.
"[Iran] is the biggest exporter of terror in the world," Netanyahu told members of his rightwing Likud party.
He said there had been a number of attempts to harm Israelis and Jews in recent months, in places such as Thailand and Azerbaijan, in a series of attacks co-ordinated by Tehran and Hezbollah.
|Israeli prime minister Netanyahu accused Iran and its ally Hezbollah of involvement in the attacks [Reuters]
Israel would continue to act "with a firm hand" to stamp out "international terror coming from Iran," he said.
An Iranian foreign ministry spokesman rejected Netanyahu's accusation, saying it was Israel that had carried out the attacks as part of its psychological warfare against Iran.
"It seems that these suspicious incidents are designed by the Zionist regime and carried out with the aim of harming Iran's reputation," the official news agency IRNA quoted Ramin Mehmanparast as saying.
Al Jazeera's Cal Perry, reporting from Jerusalem, said the attacks were "near simultaneous".
"That is going to lend weight to those who will point the finger at a larger organisation, maybe even a country like Iran, maybe Hezbollah," our correspondent said.
Al Jazeera's Prerna Suri, reporting from New Delhi, said the targeted vehicle there was parked down the street from the Israeli embassy in a high security area, about a kilometre away from the prime minister's residence.
"Witnesses discribed how the car exploded in flames. One side of the car had been completely charred. The bonnet had been flug open and exploded in flames.
"Other witnesses described two people on motorbikes throwing some kind of device [at the car], and police are trying to find out what kind of device that was. Indian forensic teams as well as Israeli embassy staff are at the scene of the incident, trying to piece together what exactly has happened," our correspondent said.
Shota Uitashvili, spokesman for the Georgian interior ministry, said the car in Tbilisi was in a car park about 200 metres from the embassy, where the driver had parked it in the morning after coming from his home.