Moments before he was fatally shot from behind on Friday, Japanese former Prime Minister Shinzo Abe was doing what he'd done for decades in politics: getting up close to the crowds and stumping for a local candidate.

As is typical in Japan, where violent crime is rare and guns are scarce, security appeared to be light on Friday morning as Abe spoke at an intersection outside the Yamato-Saidaiji Station in the western city of Nara.

Roads weren't blocked off and a bus and a van passed behind Abe's exposed back as he spoke to the crowd of a few hundred. Two helmeted riders on scooters turned in front of him. Inside a passing hatchback car, someone waved in excited recognition at Japan's longest-serving premier.

This account is based on footage obtained by Reuters and interviews with witnesses.

Dressed in a dark jacket despite the summer heat, Abe called on the crowd, many of them older, to re-elect Kei Sato, a candidate in Sunday's upper house election. Some snapped pictures with their phone or mopped their brows in the humidity.

Members of the special police, Japan's equivalent of the secret service, appeared to be standing at his right and behind him as the two-time prime minister told the crowd of Sato's pandemic response.

"He was the type of person who didn't look for reasons not to do something," Abe recalled.

Behind him, a skinny man dressed in a grey t-shirt and beige cargo pants strode into the road and opened fire with what police later said was a homemade gun, sending a cloud of white smoke towards Abe and the crowd.

For a moment, Abe appeared unaffected. The man, identified as Tetsuya Yamagami, a 41-year-old former member of Japan's maritime self-defence forces - the equivalent of Japan's navy - fired again.

Yamagami "came out of nowhere on to the middle of the road holding a gun", said businessman Makoto Ichikawa, who had been near the train station waiting for his wife.

"The first shot no one knew what was going on," Ichikawa said. After the second shot, Yamagami was tackled by the special police who pinned him down on the ground. His shirt rode up, exposing a black belt with a silver buckle. Like most people in the crowd, he wore a mask.

There was a pause of 10-20 seconds before Yamagami was tackled, said Takenobu Nakajima, who runs a printing company and was at the station to support the LDP.

By then, Abe, 67, lay crumpled on the ground. Footage from media showed blood staining his crisp white shirt.

Ken Namikawa, the mayor of Nara's Tenri city, called out over a microphone asking if there were any doctors or nurses in the crowd. A nurse came running and joined the crowd of people attending to Abe.

At least one person administered heart massage.

Doctors later said Abe bled to death from deep wounds to the heart and the right side of his neck, despite receiving more than 100 units of blood in transfusions over four hours.

Ichikawa said he was struck by Yamagami's face as he fired at the former premier.

"It was just a normal expression," he said. (Reporting by Satoshi Sugiyama; Additional reporting by Sakura Murakami and Reuters Tokyo bureau; Writing by David Dolan; Editing by Nick Macfie)