Footage showing the aftermath of a series of explosions in the Thai capital Reuters

Israel has accused Iran of being behind three blasts in Bangkok that injured five people and blew off the legs of the alleged bomber – an Iranian national who was fleeing police when the grenade slipped through his hands and detonated next to him.

The blasts came just a day after bombs targeted Israeli diplomats in India and Georgia, and has again escalated tensions between the two countries.

Thai police have not yet divulged motives for the blasts, but the Israeli defence minister, Ehud Barak, directly accused Iran of exporting terror around the world. "The attempted terror attack in Thailand proves once again that Iran and its proxies continue to operate in the ways of terror and the latest attacks are an example of that," said Barak.

He said Iran and its Lebanese ally Hezbollah were "unrelenting terror elements endangering the stability of the region and endangering the stability of the world".

A second suspect was arrested at Bangkok's Suvarnabhumi international airport after authorities found explosive materials in a house apparently rented by the bomber and two others. A third suspect is still at large, according to Thai police.

Thailand's national police chief, General Prewpan Damapong, said the bombs were "magnetic" and could be stuck on vehicles. They appeared to be intended for targeting individuals rather than buildings or large crowds.

When asked whether the explosives used in India and Thailand were the same, Thai National Security Council secretary Wichian Podphosri Wichian said: "They both have the same magnetic sheets attached to the bombs.

"The individual was in possesion of the same magnets and we are currently examining the source of the magnet."

Israel's ambassador to Thailand said they were similar to the Georgia and India bombs.

The two men in custody are likely to be closely interrogated by Thai police about their intended target and who they were working for. Israeli officials said they expected the Thai authorities would share information obtained in the course of their investigation, but declined to say whether Israel would seek an active role in the interrogation of the men.

Saeid Moradi, who was seriously injured in the blast, is an Iranian national who is thought to have entered Thailand from South Korea on 8 February at the southern resort town of Phuket. The second suspect has been named as the Iranian national Mohammed Hazaei, 42, who was detained after trying to board a flight to Malaysia, according to local media.

The first blast was at about 2pm local time on Tuesday, when a bomb accidentally detonated inside the assailant's house in Ekkamai, a bustling residential district in east Bangkok. The blast blew off part of the roof, causing two occupants to flee, police said, followed by a wounded and bloodied Moradi.

"He tried to wave down a taxi, but he was covered in blood, and the driver refused to take him," police general Pansiri Prapawat told Associated Press.

Moradi then threw a grenade at the taxi, injuring the driver and four others.

When police tried to stop the man, he threw another grenade at them, which local media reported as bouncing off a tree and detonating in front of him. One of his legs was blown off and landed in the playground of a nearby school.

Doctors at Chulalongkorn hospital, where the bomber is being treated, said the second leg had to be amputated above the knee.

A satchel found near the blast contained Iranian currency, US dollars and Thai bahts, and was inspected by a bomb disposal unit.

The Bangkok Post released a photo of the assailant after the blast, his face lacerated and bloodied from the attack. Another photo posted on Twitter just after the explosion showed a man, allegedly Moradi, lying in front of a school amid shards of glass, his body slumped on the pavement. No children were injured in the incident.

A police raid on the assailant's house found a cache of C4 explosives and remote-control detonators. These are now being investigated, the government spokeswoman Thitima Chaisaeng told the Bangkok Post.

Thai authorities said they were already alert to a potential bomb attack. "There was some warning of a possible attack and police were monitoring, but we did not know where it would happen," the Thai national police chief Phrewphan Damapong told AFP.

The city has been on edge since Thai police charged a Lebanese man suspected of planning an attack in Bangkok following a US warning of a threat of a terrorist strike on tourist areas last month, although Thai police said they had found no direct link.

Observers fear the bomb attacks in Thailand, India and Georgia are the latest acts in a covert war between Israel and Iran over the Islamic republic's nuclear ambitions. Iran has accused Israel of assassinating several of its nuclear scientists in magnet bomb attacks – the same weapon that was used to target an Israeli diplomat in Delhi on Monday, injuring four people.

In Jerusalem, the Israeli foreign ministry spokesman, Yigal Palmor, said there was not yet any sign that the targets in Bangkok were Israeli or Jewish. "Security co-operation [between Israel and Thailand] is very tight," he said.

Israel has raised the state of alert within the country, with the emphasis on public places, foreign embassies and offices, as well as Ben-Gurion international airport.

The US embassy in Bangkok released an emergency message to all US citizens in the capital, stressing the need for "heightened awareness" of any suspicious behaviour, while the Thai prime minister, Yingluck Shinawatra, urged the public not to panic, saying it was still too early to assume terrorists were responsible for the blast.

The explosions come just a month after the US embassy warned that "foreign terrorists" were poised to attack Bangkok and a Lebanese-Swedish man with alleged links to pro-Iranian Hezbollah was detained by police at Bangkok's Suvarnabhumi airport. Authorities later discovered a warehouse filled with nearly four tonnes of urea fertiliser and several gallons of liquid ammonium nitrate.

Thai authorities said then that Thailand appeared to be a staging ground but not the target of an attack.

The police general Pansiri said that so far, there were no links between last month's case and Tuesday's blasts.

Will Hartley, editor of IHS Jane's Terrorism & Insurgency Centre, said: "While Israel's claims that Iran and Hezbollah are behind the attacks in India and Georgia cannot be discounted, at this stage it's impossible to substantiate such allegations, and it is unclear why Iran would risk an attack on Israeli interests in India, when India has been broadly supportive of Iran during the recent nuclear sanctions debate, and is one of Iran's most important trade partners.

"The alleged perpetrator of today's attempted attack in Thailand reportedly possessed an Iranian passport, possibly lending credence to Israel's allegation that Iran is waging some kind of international campaign. However, the attacks in India, Georgia and now Thailand have all been highly amateurish, and lack the sophistication that would normally be expected from an operation executed by either Hezbollah or Iran's own external operations wing, the Quds Force."