JERUSALEM — Israeli officials said Wednesday that magnetic explosive devices found after a series of explosions in Bangkok on Tuesday were similar to bombs used a day earlier to target Israeli diplomats in New Delhi and in Tbilisi, Georgia.

The officials, citing findings of local investigations, said the forensic evidence buttressed earlier Israeli assertions that Iran was behind the attacks. Iran, which had threatened to retaliate for the killings of several of its nuclear scientists in similar bombings, has denied any involvement in the explosions, calling them Israeli provocations.

Thailand’s police chief said three Iranians who were arrested after accidentally setting off explosives at their rented home in Bangkok were plotting to attack Israeli diplomats, the Associated Press reported.

“I can tell you that the target was specific and aimed at Israeli diplomatic staff,” police chief Gen. Prewpan Dhamapong told a Thai television station late Wednesday.

He also confirmed that the type of explosive — a homemade “sticky” bomb — found at the blast site Tuesday matched the devices planted on Israeli diplomatic cars in India and Georgia a day earlier.

“The type of improvised explosives they used were the same. The type that was attached to vehicles,” Prewpan said, confirming that an investigation into a magnetic strip found in Bangkok was the same type used in New Delhi.

Indian and Thai authorities said earlier that they still do not have evidence that would indicate who was responsible for the blasts. Officials in Georgia have not commented on who might have been behind the bombing attempt there.

But an Israeli official familiar with the probes of the incidents, in which Israelis are working with local investigators in New Delhi, Bangkok and Tbilisi, said their findings showed a strong similarity among the bombs in the three locations, and signs of Iranian involvement.

“It looks like it’s exactly the same kind of device,” said the official, who spoke on the condition of anonymity because he was not authorized to speak publicly on the subject. He said that the way the devices were assembled, their electronic elements and other findings pointed to “an Iranian connection.” He did not elaborate.

Authorities in Thailand said their search of the house in Bangkok that had been wrecked by the explosion Tuesday uncovered magnetic explosive devices with a destruction capacity aimed at individuals, not large crowds or buildings, according to news agency accounts.

Thai police arrested two of three Iranian men who fled the house after the blast. One man lost a leg when he hurled a grenade at police, and the second was detained as he tried to board a flight to Malaysia. The third man was arrested in Malaysia on Wednesday.

The Israeli ambassador to Thailand, Itzhak Shoham, told the Associated Press that Thai police had found two magnetic bombs that could be stuck on vehicles. “They are similar to the ones used in Delhi and Tbilisi,” Shoham said.

He said that while the target was unclear, “we can assume from the other experiences that we were the target.”

In the attack in New Delhi on Monday, a magnetic bomb was slapped onto an Israeli diplomatic vehicle by a passing motorcyclist. It detonated, wounding the driver and the passenger, an embassy employee who is married to an Israeli defense envoy.

In Tbilisi, a similar device was found attached with a magnet to the underside of a car belonging to a driver who works at the Israeli Embassy. It was safely defused.

The attacks were strikingly reminiscent of the bombings — also featuring the use of magnetic devices — that have killed several Iranian scientists.

In remarks carried by Iran’s news agency, Iranian Foreign Ministry spokesman Ramin Meh­manparast accused Israel of orchestrating the string of explosions this week “to conceal its real essence in carrying out terrorist acts, particularly assassinating Iran’s scientists.”

Israeli Prime Minister Benjamin Netanyahu, who convened his security cabinet to discuss the recent blasts, said that they had “exposed Iran’s terrorist acts for all to see.”

“Iran undermines stability in the world, harms innocent diplomats in many countries, and the nations of the world must condemn the Iranian terror actions and draw red lines against the Iranian aggression,” Netanyahu said. “If such aggression is not stopped, it will spread to many countries.”