Former Japanese prime minister Shinzo Abe was feared dead on Friday after apparently being shot at a campaign event in the Nara region, local media reported.
National broadcaster NHK said a man in his 40s had been arrested for attempted murder and a gun had been confiscated from him, citing police sources.
The former leader had been delivering a stump speech at an event ahead of Sunday's upper house elections when the apparent sound of gunshots was heard, NHK and the Kyodo news agency said.
"He was giving a speech and a man came from behind," a young woman at the scene told NHK.
"The first shot sounded like a toy. He didn't fall and there was a large bang. The second shot was more visible, you could see the spark and smoke," she added.
"After the second shot, people surrounded him and gave him cardiac massage."
Abe, 67, collapsed and was bleeding from the neck, a source from his ruling Liberal Democratic Party told the Jiji news agency.
Neither the LDP nor local police were able to immediately confirm the reports.
NHK and Kyodo both reported Abe was taken to hospital and appeared to be in cardo-respiratory arrest -- a term used in Japan indicating no vital signs, and generally preceding a formal certification of death by a coroner.
Several media outlets reported that he appeared to have been shot from behind, possibly with a shotgun.
The government said a task force had been formed in the wake of the incident and the top government spokesman was expected to speak shortly.
Abe, Japan's longest-serving prime minister, held office in 2006 for one year and again from 2012 to 2020, when he was forced to step down due to the debilitating bowel condition ulcerative colitis.
Japan has some of the world's toughest gun-control laws, and annual deaths from firearms in the country of 125 million people are regularly in single figures.
Getting a gun licence is a long and complicated process even for Japanese citizens, who must first get a recommendation from a shooting association and then undergo strict police checks.
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