The explosion at Miyazaki Airport caused a crater seven metres wide and one metre deep in the middle of the taxiway next to the runway
Police in Denmark and Sweden said on Wednesday they were probing explosions and gunfire around Israeli embassies in their capitals which took place amid spiralling Middle East tensions.
In Denmark, police said three Swedish nationals had been arrested after two blasts were reported in the "immediate proximity" of the Israeli embassy in Copenhagen in the early hours of Wednesday.
Swedish said the Israeli embassy in Stockholm had been targeted in a shooting on Tuesday just before 6pm.
No injuries were reported from the incidents but both came amid heightened international fears as Iran fired missiles at Israel which has vowed to respond to the attack.
"Two explosions occurred at 3.20am at the Israeli embassy. It is our preliminary assessment that it was due to two hand grenades," Jens Jespersen of the Copenhagen police told a press conference.
He added that three Swedes aged between 15 and 20 had been arrested.
The police officer explained that one suspect was arrested shortly after the incident, near the crime scene, and that the other two had been arrested later.
Police said in a earlier statement that two suspects had been arrested on a train at Copenhagen Central Station.
"It's too early to say if there is a link" between the blasts and the Israeli embassy, Danish police spokesman Jakob Hansen said of the Copenhagen incidents.
By mid-morning, the area in Copenhagen was cordoned off and police were working at the scene, an AFP correspondent observed.
Denmark's intelligence service PET said it was monitoring events "closely" and assisting the police investigation.
"We are also in dialogue with the Israeli embassy about security, and are constantly assessing the scale of the security measures already implemented in relation to a number of Jewish locations," PET said in a statement.
Writing on X, Israel's Ambassador to Denmark David Akov said he was "shocked by the appalling incident near the embassy a few hours ago".
Swedish police said in a statement that information indicated the Israeli embassy building had been hit by shots on Tuesday evening.
"We've made finds that indicate a shooting at Israel's embassy, but we don't want to disclose exactly what finds have been made since there is an ongoing investigation," said Rebecca Landberg, Stockholm police press officer.
Landberg added that an investigation had been opened into an aggravated weapons offence, endangerment of others and unlawful threats.
Police had made no arrests, but Landberg said police were actively gathering and analysing material from the many surveillance cameras in the area.
Since the outbreak of the Israel-Hamas war in October 2023, several incidents apparently targeting Israeli interests in Sweden have been reported.
In February, police found a grenade in the Israeli embassy compound grounds, which the ambassador said was an attempted attack.
In May, gunshots were fired outside the Israeli embassy, which prompted Sweden to boost security around Israeli interests and Jewish community institutions.
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