Afghan police say gunmen who killed a prominent Japanese doctor on Wednesday may have had a strong intent to kill, as they fired automatic rifles several times at him.

Tetsu Nakamura was fatally shot in Jalalabad in the eastern province of Nangarhar. Five other people who were travelling with him were also killed in the attack. They include the driver and bodyguards.

An eyewitness at the scene of the attack said men in a Japanese car blocked Nakamura's vehicle and some of them got out and began shooting.

The police say the men approached Nakamura, who was seated in the passenger's seat, and shot him several times with automatic rifles at a range of about 10 meters.

They add that Nakamura was hit by two bullets in the torso.

Nakamura's body was transferred to a military hospital in the capital Kabul. His relatives and members of his aid group based in Fukuoka Prefecture, western Japan, are on their way to Afghanistan to bring the body back to Japan.

Nakamura was 73 years old. He was the representative of the Afghan branch of the non-governmental organization Peshawar-kai.

He had spent years in Afghanistan, offering humanitarian support and helping with recovery efforts.