Prime minister of Japan, Fumio Kishida, was unharmed while leaving a public function after what appeared to be a smoke bomb was hurled in his direction.
Local media said that a guy was apprehended on the spot in Wakayama, where Mr. Kishida was scheduled to deliver a speech.
A witness said they saw a person throwing something, followed by smoke, while another said they heard a big bang. No injuries were reported.
Video showed officers piling on top of a person, believed to be a suspect.
He was arrested on suspicion of obstruction of business and later identified by the authorities as 24-year-old Ryuji Kimura. His motivation is still unclear.
Japan’s public broadcaster, NHK, quoted Mr Kishida as saying there was a “loud blast” at the venue. “Police are investigating details, but I’d like to apologise for worrying many people and causing them trouble.”
NHK broadcast footage in which crowds of people appear to be running away from the scene.
The footage also shows people swarm around one man, hold him down, and then carry him away.