Japan's former prime minister Shinzo Abe has died at the age of 67 after being shot while campaigning.
It is the first assassination of a sitting or former Japanese prime minister since the 1930s.
Abe had been delivering a speech near a train station in the western city of Nara, when he was shot by an assailant at about 11.30am local time, chief Cabinet secretary Hirokazu Matsuno said on Friday.
He was flown to hospital, where he was not breathing and his heart stopped, officials said.
Authorities arrested a man believed to have shot Abe in the back. Officers later raided the accused man's home.
Japan's Prime Minister Fumio Kishida said he was "lost for words" after the assassination.
"I was praying that his life would be saved, but despite that, I came to learn of [his death]," he said. "It is truly regrettable. I am lost for words. I offer my sincere condolences and prayers that his soul may rest in peace."
Public broadcaster NHK aired footage that showed Abe holding his chest on the ground, his shirt smeared with blood, as several security guards ran towards him.
Then security guards leapt on top of a man in a grey shirt, lying face down on the pavement. A double-barrelled device that appeared to be a handmade gun could be seen on the ground.
Nara prefectural police confirmed the arrest of Tetsuya Yamagami, 41, on suspicion of attempted murder. NHK reported that the suspect had served in the Maritime Self-Defence Force for three years in the 2000s.
NHK said two consecutive gunshots were heard during Abe's campaign speech before Sunday’s vote to elect politicians to the country's upper house of Parliament.
Nara emergency services said he had been wounded on the right side of his neck and left clavicle. His brother, Defence Minister Nobuo Kishi, had said Abe was receiving blood transfusions.
NHK showed live footage of Abe's wife, Akie, on her way by train to the hospital where he was being treated.
'Never been anything like this'
Airo Hino, a political science professor at Waseda University, said such a shooting was unprecedented in Japan.
“There has never been anything like this,” he said.
Abe served two terms to become the country's longest-serving prime minister before stepping down in 2020 due to ill health.
He remained a dominant presence over the ruling Liberal Democratic party, controlling one of its major factions.
"During this election period, a despicable and barbaric act was committed, taking the life of former prime minister Abe. This is unforgivable. We condemn it once again in the strongest terms," Mr Kishida said.
Election activities will continue with "full and thorough measures" taken to ensure safety, said Mr Kishida, the leader of the ruling Liberal Democratic Party (LDP) of which Abe was also a member.
"We must absolutely defend free and fair elections, which are the basis of democracy," he said. "We will proceed with our election campaign tomorrow as planned with the firm conviction that we will never yield to violence."
Abe "assumed a heavy responsibility as prime minister for eight years and eight months", the longest period in modern history, said Mr Kishida.
"He guided the country in the face of a difficult domestic and international situation through his outstanding leadership and executive ability."