Thai investigators are examining a possible link in a bizarre series of explosions in Bangkok and botched attacks targeting Israeli embassy staff in India and Georgia, a senior security official said on Wednesday.
Israel accused Iran and its Lebanese ally Hezbollah of being behind the attacks. Iran strongly denies involvement.
A man carrying an Iranian passport lost a leg when a bomb he was carrying in Bangkok went off on Tuesday after an earlier explosion, apparently accidental, at a house he was renting.
His second leg had to be amputated.
A day earlier in the Indian capital, a bomb wrecked a car taking an Israeli embassy official to pick up her children from school, police said. The woman was in stable condition on Wednesday after surgery to her spine and liver.
Her driver and two passers-by suffered lesser injuries in the attack which police believe was also a botched job.
The motorbike rider who stuck the bomb on to the car put it on the opposite side to the petrol tank -- if it had been on the tank side it would have been a bigger blast and likely caused fatalities.
Israeli officials said an attempt to bomb an embassy car in the Georgian capital Tbilisi failed and the device was defused.
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 possession of the same magnets and we are currently examining the source of the magnet.
One bomb went off in their Bangkok home. Another was thrown at a cabbie that wouldn't take them, drawing more attention. Another was thrown towards police but hit either a tree or a truck and bounced back, blowing off the bomber's leg.
Two other men shared the rented house with him. One was arrested at Bangkok's international airport on Tuesday but the third had slipped past security at the airport and fled to Malaysia, Wichian said.
India media quoted Delhi Police Commissioner B.K. Gupta as saying that a sticky bomb not bigger than a palmtop or brick was stuck to the car and would have exploded three to five seconds later.
Investigators have recovered magnetic material that formed part of the bomb from the scene.
Indian media said investigators were scanning records of all Iranian nationals as well as Lebanese students who arrived in the country in recent months.
Thai police declined to make any link between Tuesday's explosions and the arrest last month of a Lebanese man in Bangkok who, according to the Thai authorities, had links to Hezbollah.
The police discovered a large amount of explosive material in an area southwest of Bangkok at around the time of that arrest. The United States, Israel and other countries issued warnings, subsequently lifted, of possible terrorist attacks in areas frequented by foreigners.
(Reporting by Pracha Hariraksapitak, Panarat Thepgumpanat and Sinsiri Tiwutanond in Bangkok; John Chalmers in New Delhi; Writing by Nick Macfie and Alan Raybould, Editing by Jonathan Thatcher)